{"id":10127,"date":"2023-07-29T07:57:07","date_gmt":"2023-07-29T11:57:07","guid":{"rendered":"https:\/\/dronebotworkshop.com\/?p=10127"},"modified":"2023-07-29T07:57:07","modified_gmt":"2023-07-29T11:57:07","slug":"arduino-uno-r4-minima-wifi","status":"publish","type":"post","link":"https:\/\/dronebotworkshop.com\/arduino-uno-r4-minima-wifi\/","title":{"rendered":"Arduino Uno R4 &#8211; Minima &#038; WiFi"},"content":{"rendered":"\n<p><a href=\"https:\/\/s3.amazonaws.com\/download.dronebotworkshop.com\/DBWS+-+PDF+-+Arduino+Uno+R4+Boards.zip\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-9571 size-full\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/04\/dbws-pdfdown.png?resize=64%2C64&#038;ssl=1\" alt=\"Download PDF\" width=\"64\" height=\"64\" data-recalc-dims=\"1\" \/><\/a> <a href=\"#Parts_List\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-9563 size-full\" title=\"Parts List\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/04\/dbws-parts.png?resize=64%2C64&#038;ssl=1\" alt=\"Parts List\" width=\"64\" height=\"64\" data-recalc-dims=\"1\" \/><\/a> <a href=\"https:\/\/youtu.be\/kJE9CBb3fT8\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-9565 size-full\" title=\"View on YouTube\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/04\/dbws-youtube.png?resize=64%2C64&#038;ssl=1\" alt=\"View on YouTube\" width=\"64\" height=\"64\" data-recalc-dims=\"1\" \/><\/a><\/p>\n<p><span style=\"font-weight: 400;\">Today we will look at the latest member of the popular Arduino Uno line of microcontrollers, the Arduino Uno R4. With this release, Arduino has produced two boards &#8211; the <\/span><a href=\"https:\/\/docs.arduino.cc\/hardware\/uno-r4-minima\" target=\"_blank\" rel=\"noopener\"><b><i>Minima<\/i><\/b><\/a><span style=\"font-weight: 400;\"> for budget-conscious users and the <\/span><a href=\"https:\/\/docs.arduino.cc\/hardware\/uno-r4-wifi\" target=\"_blank\" rel=\"noopener\"><b><i>WiFi<\/i><\/b><\/a><span style=\"font-weight: 400;\"> with all the bells and whistles.\u00a0<\/span><\/p>\n<div class=\"youtube-player\" data-id=\"kJE9CBb3fT8\"><\/div>\n<h2><span style=\"font-weight: 400;\">Introduction<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The Arduino Uno was officially released in October 2010 as a replacement for the Arduino Duemilanove. The Uno offered several improvements over the Duemilanove, and it soon became one of the most popular microcontrollers in the world, especially among makers and hobbyists.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10128\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-Boards.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-Boards.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-Boards.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Since its initial release, the Arduino Uno has undergone a number of updates:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Arduino Uno (Revision 1)<\/b><span style=\"font-weight: 400;\"> &#8211; Released in October 2010. The initial version of the Arduino Uno featured a removable Atmel ATmega328 microcontroller and used the Atmel ATmega8U2 for USB connectivity.\u00a0 Note that Atmel is now Microchip.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Arduino Uno (Revision 2)<\/b><span style=\"font-weight: 400;\"> &#8211; This revision added four solder pads connecting two of the ATmega8U2&#8217;s pins. This allowed the ATmega8U2 to be replaced with a standalone circuit once the development phase was complete.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Arduino Uno (Revision 3)<\/b><span style=\"font-weight: 400;\"> &#8211; Released in November 2011. This was a major revision that changed the USB chip to an ATmega16U2 and added more pin headers for compatibility with future hardware. This revision is still available and has been \u201ccloned\u201d by many manufacturers. When people speak about \u201can Arduino,\u201d this is the board they are talking about.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Arduino Uno WiFi (Revision 2)<\/b><span style=\"font-weight: 400;\"> &#8211; Released in 2018, this variant of the Uno added built-in WiFi connectivity through an ESP32 module. In addition to WiFi, it also offered enhanced features like a 6-axis IMU, temperature sensor, and crypto chip for secure communication.\u00a0 It was never very popular, but it is still available.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">There were also several &#8220;special edition&#8221; Arduino Unos produced, such as the <\/span><b>Arduino Uno SMD Edition<\/b><span style=\"font-weight: 400;\"> (which replaced the removable DIP ATmega328 chip with a surface-mount version) and the <\/span><b>Arduino Genuino Uno<\/b><span style=\"font-weight: 400;\"> (\u201cGenuino\u201d was the name under which the Uno was sold outside the USA for some time due to legal complications).<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Now, in mid-2023, we finally have a new revision of the Arduino Uno. Actually, we have two.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Let\u2019s see if it was worth the wait!<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">The Arduino Uno R4 Boards<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Instead of just a single board, the new Arduino Uno R4 has been released as two.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>The Uno R4 WiFi<\/b><span style=\"font-weight: 400;\"> &#8211; A board with all the \u201cbells and whistles\u201d.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>The Uno R4 Minima<\/b><span style=\"font-weight: 400;\"> &#8211; A less expensive, \u201cstripped-down\u201d version.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">As of this writing, July 2023, the Minima retails for USD 20.00, while the WiFi version will set you back USD 27.50.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Each board is packaged with a clear plastic carrier, which is handy for experimenting.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Board Characteristics<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The first thing you will notice about the new Uno R4 is that it has an almost identical form factor to the Version 3 Uno, including the female Dupont connectors and mounting holes. The USB connector has changed, which is unsurprising, as the Uno 3\u2019s USB-A connector was outdated when it was released 12 years ago. The new boards use USB-C connectors.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The barrel jack is still there, and this time it accepts a wider range of input voltages.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The Minima board has a pretty sparse design, with lots of empty real estate on the PCB.\u00a0 In contrast, the WiFi board is very populated, with much of its board space occupied by a 12 x 8 matrix of LEDs.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The connectors are all clearly labeled, and there are a few extra connectors as well.\u00a0 The WiFi board has connectors for accessing its internal ESP32 processor and a QWIIC connector for I2C.\u00a0 The Minima has a diagnostic connector, and both boards have the familiar ICSP connector for SPI.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">As expected from an Arduino product, the build quality of both boards is excellent.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">5-Volt Operation<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">To maintain compatibility with the older Arduino Uno boards, the new R4 boards use 5-volt logic.\u00a0 This is not very common in 2023, as almost every new microcontroller board is a 3.3-volt device, but it does have the advantage of allowing the R4 boards to accept existing Uno shields.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The QWIIC connector on the WiFi board is a 3.3-volt I2C bus and is not 5-volt tolerant.\u00a0 The ESP32 Header, which allows direct connection to the onboard ESP32, is also a 3.3-volt logic connection.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Powering up the boards<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The new Uno R4 boards operate internally at 5 volts but can be powered in several different ways:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>USB-C Connector<\/b><span style=\"font-weight: 400;\"> &#8211; The board uses 5 volts from the USB-C input.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Barrel Connector<\/b><span style=\"font-weight: 400;\"> &#8211; The same 2.1mm barrel connector used on the R3 boards (center is positive) can be used with voltages from 6 volts to 24 volts.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>VIN pin<\/b><span style=\"font-weight: 400;\"> &#8211; You can also apply 6\u201324 volts to the VIN pin; essentially, this is the same as using the barrel connector.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Renesas RA4M1 Microcontroller<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The new Arduino Uno R4 boards employ the Renesas RA4M1 microcontroller.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This is a 48 MHz Arm-Cortex MPU with 32 kB of SRAM, 256 kB of Flash memory, and 8 KB of EEPROM.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The MPU features a number of timers, including a Watchdog Timer and a Real Time Clock.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">It has many analog interface options, including 25 14-Bit Analog to Digital Converters, one 12-Bit Digital to Analog Converter, four Operational Amplifiers, two Comparators, and an internal temperature sensor.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">It also has an abundance of communications options, including two I2C (Integrated Integrated Circuit), two SPI (Serial Peripheral Interface), four SCI (Serial Communications Interfaces, also called UART), and one SSI (Serial Synchronous Interface, also called USART)port.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Note that the Arduino Uno R4 boards do not expose all the capabilities of the RA4M1.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This microcontroller can be booted up in two different modes:<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10180\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Renesas-RA4M1.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Renesas-RA4M1.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Renesas-RA4M1.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Single-Chip Mode<\/b><span style=\"font-weight: 400;\"> &#8211; This is the default mode. In this mode, the microcontroller boots up normally and connects to the USB port for use with an IDE.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>SCI\/USB Mode<\/b><span style=\"font-weight: 400;\"> &#8211; In this mode, the microcontroller boots up as a USB peripheral. This allows for HID (Human Interface Device) emulation and sharing storage with an external computer.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Uno R3 &#8211; R4 Feature Comparison<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Here is a quick look at the key features that differ between the Arduino Uno R3 and R4 boards.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10131\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-vs-R3.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-vs-R3.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-vs-R3.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">As the chart shows, the R4 models are superior to the R3 in virtually every way, with one notable exception.<\/span><\/p>\n<h3><b>Warning &#8211; 8 mA Current Limitation!<\/b><\/h3>\n<p><span style=\"font-weight: 400;\">The one difference between the new R4 boards and the older Uno\u2019s that you must be aware of is the pin current limitation.<\/span><\/p>\n<p><b>On the new Arduino Uno R4 boards, the maximum source\/sink current is 8 milliamperes. On the older R3 boards, it was 20 mA.\u00a0<\/b><\/p>\n<p><b>In other words, the new Arduino Uno R4 boards can only handle about 40% of the current on its I\/O pins than the older Arduino Uno R3 could!<\/b><\/p>\n<p><span style=\"font-weight: 400;\">For driving other digital logic devices and displays like OLED\u2019s this limitation is irrelevant; 8ma is plenty of current for logic circuitry. But it&#8217;s a different story when powering an LED.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">Powering LEDs with the New Uno\u2019s<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">In many circuit diagrams, including ones here in the DroneBot Workshop, you\u2019ll see LEDs connected to microcontroller I\/O pins using a dropping resistor with a value of 150 to 330 ohms. Most of the circuits I\u2019ve designed use 220 ohms, and that\u2019s a pretty popular value as it handles the voltage drop and current of virtually every discreet LED.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">With a 220 ohm dropping resistor, a standard red LED will pull about 12 mA from a 5-volt digital I\/O pin.\u00a0 And that exceeds the 8 mA limitation of the new Arduino Uno R4 boards.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">I hooked up an LED with a dropping resistor to pin D13 on an Arduino Minima so that I could run the fascinating Blink sketch. I used a 1k resistor and had no problem seeing an LED. Tried it with different colors of 5mm LEDs, and they all worked.\u00a0 In this configuration, the LED pulled about 3 mA, well within the accepted range of the Arduino R4 digital I\/O pins.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10176\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/led-dropping-resistor.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/led-dropping-resistor.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/led-dropping-resistor.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">As a rule of thumb, try not to use a dropping resistor of less than 470 ohms. This will draw about 6 mA from the I\/O pin, assuming your LED has a dropping voltage of about 2 volts.\u00a0 For LEDs with higher voltage drops, you can reduce the value to as low as 330 ohms.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Just stay away from the 220 ohm dropping resistors, and you\u2019ll be fine!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If you\u2019d like to compute the actual resistor value for your LED, you\u2019ll need to know the LED&#8217;s voltage drop. Armed with that information, you can use the <\/span><a href=\"https:\/\/www.digikey.ca\/en\/resources\/conversion-calculators\/conversion-calculator-led-series-resistor\"><span style=\"font-weight: 400;\">LED Dropping Resistor Calculator at DigiKey<\/span><\/a><span style=\"font-weight: 400;\"> to calculate the value of your resistor.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Arduino Uno R4 Pinouts, Connectors, and Features<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Here is an in-depth look at the pinouts, connectors, and features of the Arduino Uno R4 boards. Most of the pins and connectors are common to the Minima and WiFi boards; however, in some cases, the pinouts are exclusive to one board. This is noted in the diagrams and descriptions.<\/span><\/p>\n<p><b>If you want a big diagram of the Uno R4 Minima, <\/b><a href=\"https:\/\/docs.arduino.cc\/static\/7501e2ad784ed34f331afae4947e06fd\/ABX00080-pinout.png\" target=\"_blank\" rel=\"noopener\"><b>Arduino has one here<\/b><\/a><b>.<\/b><\/p>\n<p><b>For a large drawing of the Uno R4 Wifi, <\/b><a href=\"https:\/\/docs.arduino.cc\/static\/a7dae6b1794d22127c82764ce5969317\/ABX00087-pinout.png\" target=\"_blank\" rel=\"noopener\"><b>you can click here<\/b><\/a><b>.<\/b><\/p>\n<h3><span style=\"font-weight: 400;\">Power In &amp; Out<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">In addition to having power connections, the Uno R4 boards also output voltages at low currents.\u00a0 These mimic the same outputs in the Uno R3.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10148\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The connections on the side are as follows:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>VIN<\/b><span style=\"font-weight: 400;\"> &#8211; This is the input voltage used for powering the board. It can be any DC voltage in the range of 6 to 24 volts.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>GND<\/b><span style=\"font-weight: 400;\"> &#8211; Two ground connections.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>5V<\/b><span style=\"font-weight: 400;\"> &#8211; This is a 5-volt output used to power external peripherals.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>3V3<\/b><span style=\"font-weight: 400;\"> &#8211; A 3.3-volt output, also used for external low-current devices.<\/span><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10147\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power-In.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power-In.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Power-In.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">There are also power connections on the top of the board:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>2.1mm Jack<\/b><span style=\"font-weight: 400;\"> &#8211; This barrel jack can accept voltages from 6 to 24 volts; it is internally connected to the VIN pin.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>USB-C<\/b><span style=\"font-weight: 400;\"> &#8211; The USB-C connector can be used for both communications and power. It supplies 5 volts.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Power &amp; RTC (WiFi Only)<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Although the Real Time Clock RTC) is included on both boards, only the WiFi board has connections for a battery backup.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10150\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-RTC.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-RTC.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-RTC.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>VRTC<\/b><span style=\"font-weight: 400;\"> &#8211; This is a connection for a small (I have used 3 volts) battery to back up the real-time clock.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>GND<\/b><span style=\"font-weight: 400;\"> &#8211; A Ground Connection<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>OFF<\/b><span style=\"font-weight: 400;\"> &#8211; This connection allows you to control the power on the board; when held LOW, the board will turn off. This allows you to implement a power switch on your project.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Boot &amp; Reset<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">There are a few pins that are related to the boot process:<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10149\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Reset.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Reset.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Reset.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>BOOT<\/b><span style=\"font-weight: 400;\"> &#8211; This pin was originally used to change the Boot Mode of the processor; however, in the Arduino Uno R4 boards, this is not connected. It is also unlabeled and is only there for compatibility with older shields.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>IOREF<\/b><span style=\"font-weight: 400;\"> &#8211; This pin is an output and is connected to 5 volts. Its purpose is to provide a voltage reference for the board&#8217;s logic level.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>RESET<\/b><span style=\"font-weight: 400;\"> &#8211; This pin resets the microcontroller when held LOW.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">There is also a <\/span><i><span style=\"font-weight: 400;\">Reset<\/span><\/i><span style=\"font-weight: 400;\"> button on the top corner of the board.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Bottom Connectors &amp; LED<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">There are a couple of connectors and an LED at the bottom of the board.\u00a0<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10135\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Board-End.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Board-End.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Board-End.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<h4><span style=\"font-weight: 400;\">Power LED<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The power LED is at the bottom of the WiFi board and is located a bit further inward on the Minima. It illuminates when the correct power supply voltage is applied to the board.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">ICSP Connector<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The ICSP, or \u201cIn-Circuit Serial Programming\u201d connection, was a feature on the Arduino Uno R3 boards, as well as the original 8-bit Nano boards.\u00a0 It provides an SPI bus connection.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">QWIIC (WiFi Only)<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The QUIIC connector allows for simplified connection of peripherals with compatible connections. This is an I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C connection, so several devices can be connected as long as they each have unique I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C addresses.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Two things to note about using the QUIIC connector:<\/span><\/p>\n<ul>\n<li aria-level=\"1\"><b>This is a 3.3-volt I2C bus. Do not connect it to 5-volt peripherals!<\/b><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">This connection uses the second I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C port, so existing sketches must be modified if you wish to use QUIIC devices.<\/span><\/li>\n<\/ul>\n<h4><span style=\"font-weight: 400;\">SWD \/ JTAG (Minima Only)<\/span><\/h4>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10152\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SWD.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SWD.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SWD.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">This 10-pin connector is for the connection of external diagnostic and debug equipment. It is only found on the Minima.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Analog In<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">As with the original Uno, these boards have six ADC inputs.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10134\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">By default, the Analog to Digital converter will work at 10 bits; however, you can change the resolution to 12 or 14 bits using the<\/span><i><span style=\"font-weight: 400;\"> analogReadResoloution <\/span><\/i><span style=\"font-weight: 400;\">command.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>A0 &#8211; A5<\/b><span style=\"font-weight: 400;\">\u00a0 &#8211; Analog Inputs, maximum 5-volts or <\/span><i><span style=\"font-weight: 400;\">AREF<\/span><\/i><span style=\"font-weight: 400;\"> voltage.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Analog Out<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Unlike the older R3 boards, the new Arduino Uno R4 boards have a Digital to Analog Converter, or DAC.\u00a0 This is a single-channel DAC and provides an output voltage ranging from 0 to 5 volts.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10138\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-DAC.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-DAC.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-DAC.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>A0 &#8211; DAC Output<\/b><span style=\"font-weight: 400;\"> &#8211; Output of 12-bit DAC.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C Bus<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The new Arduino Uno R4 boards have two I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C interfaces.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10143\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Interface 0 is connected the same way that it was on the earlier Uno boards, to two of the Analog pins and to a separate set of pins at the top of the Digital I\/O connector.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10142\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C-2.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C-2.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-I2C-2.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Interface 1 is connected to the QUIIC connector &#8211; remember, this is a 3.3-volt connection. It can also be programmatically connected to the existing I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C connections, this time at a 5-volt logic level.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">OP-Amp<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The Renesas RA4M1 MCU has four internal operational amplifiers, one of which is brought out to the pins on the Uno R4 boards.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10146\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-OpAmp.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-OpAmp.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-OpAmp.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The op-amp can be programmatically controlled and is for use with the Analog to Digital Converters. This can increase the input sensitivity of the ADCs, which is especially useful for audio designs.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>A1 &#8211; Positive Input<\/b><span style=\"font-weight: 400;\"> &#8211; Op-amp positive input.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>A2 &#8211; Negative Input<\/b><span style=\"font-weight: 400;\"> &#8211; Op-amp negative input.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>A3 &#8211; Output<\/b><span style=\"font-weight: 400;\"> &#8211; Op-amp output.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Digital I\/O<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The new Arduino Uno R4 boards have the same Digital I\/O ports used on the R3 version. As with the R3, six of the pins are PWM (Pulse Width Modulation) capable.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Actually, most of the pins are really PWM capable; however, the timing registers used on the pins not stated as \u201cPWM-capable\u201d are used for other purposes. It is advisable only to use the designated pins for PWM.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10139\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-1.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-1.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-1.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10140\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-2.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-2.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Digital-2.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D0 &#8211; D13<\/b><span style=\"font-weight: 400;\"> &#8211; Digital GPIO pins.\u00a0<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">UART<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The UART, or hardware serial port, is one area where the R4 boards differ from their R3 cousins.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10153\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-UART.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-UART.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-UART.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">In the R3, there was one UART, and it was connected to both the USB connector and to pins D0 and D1.\u00a0 The R4 uses two hardware serial ports, one connected to USB and the other to D0 and D1.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The consequence is that<strong> any code that expects to exchange serial data over D0 and D1 needs to use the <\/strong><\/span><strong><i>Serial1<\/i> object instead of the <i>Serial<\/i><\/strong><span style=\"font-weight: 400;\"><strong> object<\/strong>.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D0 (TX)<\/b><span style=\"font-weight: 400;\"> &#8211; The TXD1 Output<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D1 (RX)<\/b><span style=\"font-weight: 400;\"> &#8211; The RXD1 Input<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">SPI Bus<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Four digital I\/O pins are also used for the SPI bus connections. This is the same configuration used with the Uno R3.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10151\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SPI.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SPI.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-SPI.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D10 &#8211; SSLA0<\/b><span style=\"font-weight: 400;\"> &#8211; Chip Select<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D11 &#8211; COPIA<\/b><span style=\"font-weight: 400;\"> &#8211; Controller Out, Peripheral In<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D12 &#8211; CIPOA<\/b><span style=\"font-weight: 400;\"> &#8211; Controller In, Peripheral Out<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D13 &#8211; RSPCKA<\/b><span style=\"font-weight: 400;\"> &#8211; Clock signal<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">CAN Bus<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">A Controller Area Network (CAN Bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other. The Arduino Uno R4 boards have a single CAN Bus connection.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Note that this connection cannot be physically connected directly to a CAN Bus. Instead, you will require a transceiver to change the logic level signals to CAN Bus-compatible ones. The Arduino hardware and libraries take care of bus protocol and data formatting.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">One rather odd issue is that the CAN Bus connections on the Minima and WiFi boards are different!<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10136\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-Minima.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-Minima.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-Minima.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><b>Minima<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D4 &#8211; CAN TX<\/b><span style=\"font-weight: 400;\"> &#8211; CAN BUS Transmit<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D5 &#8211; CAN RX<\/b><span style=\"font-weight: 400;\"> &#8211; CAN BUS Receive<\/span><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10137\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-WiFi.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-WiFi.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-CAN-WiFi.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><b>WiFi<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D10 &#8211; CAN TX<\/b><span style=\"font-weight: 400;\"> &#8211; CAN BUS Transmit<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>D13 &#8211; CAN RX<\/b><span style=\"font-weight: 400;\"> &#8211; CAN BUS Receive<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Analog Reference Voltage<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">As with the earlier Uno boards, as well as many other Arduino boards, there is a connection for an analog reference voltage.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">By default, the ADC uses the power supply voltage of 5 volts as its reference. However, you can apply a precision voltage that does not exceed 5 volts to this pin to change the analog reference point.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This can be useful to expand the range of the ADC when using low voltages, or to increase the precision of the ADC results.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10133\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog-Ref.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog-Ref.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-Analog-Ref.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>AREF<\/b><span style=\"font-weight: 400;\"> &#8211; Analog Reference Voltage<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">Status LEDs<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">There are three status LEDs on the top right of the board; these are identical in function to the ones on the older Arduino Uno R3 boards.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10145\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Status.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Status.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Status.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>L<\/b><span style=\"font-weight: 400;\"> &#8211; Status indicator for data pin D13. Referred to as <\/span><i><span style=\"font-weight: 400;\">LEDBUILTIN<\/span><\/i><span style=\"font-weight: 400;\"> in code.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>TX<\/b><span style=\"font-weight: 400;\"> &#8211; Transmit status for USB port.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>RX<\/b><span style=\"font-weight: 400;\"> &#8211; Receive status for USB port.<\/span><\/li>\n<\/ul>\n<h3><span style=\"font-weight: 400;\">ESP32 Header (WiFi Only)<\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10141\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-ESP32.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-ESP32.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-ESP32.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The ESP Header allows direct access to a few of the GPIO pins on the onboard ESP32-S3 MCU. You can use this connection, or some of the pads on the underside of the board, to program the ESP32 independently of the Renesas RA4M1.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">LED Matrix (WiFi Only)<\/span><\/h3>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10144\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Matrix.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Matrix.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/Arduino-Uno-R4-Pinouts-LED-Matrix.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Other than its wireless capabilities, the feature that distinguishes the Arduino Uno WiFi board from all others is the large 12 x 8 LED display matrix that occupies about a quarter of the printed circuit board real estate.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Using the Arduino Uno R4 Minima<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">We will begin by examining the Arduino Uno R4 Minima. Keep in mind that, aside from the SWD connector, every feature on the Minima is also included on the WiFi board. You can use these instructions with the WiFi board if you don\u2019t have a Minima; note the difference in CAN Bus connections between the boards.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Getting started with the Minima<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The first thing you\u2019ll need to do with any of these boards is to install the boards manager. Both of the boards use the same one, and it is easily installed within the Arduino IDE.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">I\u2019ll illustrate everything with Version 2 of the Arduino IDE, but you can also use the board with the classic version 1.8 if you prefer.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">IDE Setup<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">I\u2019ll assume that you already have the Arduino IDE installed and working on your computer.\u00a0 You can use Windows, macOS, or Linux; everything is operating system independent.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Open the IDE and then open the Boards Manager by clicking the second icon from the top on the left sidebar of the IDE (the one that looks like a microcontroller board).\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">In the search box, type \u201cuno\u201d. This should return a list of board managers, including one by Arduino for the Arduino Uno R4 boards. Just click the <\/span><i><span style=\"font-weight: 400;\">Install<\/span><\/i><span style=\"font-weight: 400;\"> button to add it to your IDE.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10181\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-board-manager.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-board-manager.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-board-manager.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">You can test the installation by attaching your board and configuring the IDE for the correct port. Select the Uno Minima or WiFi board, depending upon which one you have.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Now open the File menu and go to Examples. Scroll down to the \u201c<\/span><i><span style=\"font-weight: 400;\">Examples for Arduino R4 Minima<\/span><\/i><span style=\"font-weight: 400;\">\u201d (or WiFi ) and take a look at the wealth of sample sketches you can run and learn from!<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">DAC &#8211; Sine Wave Generation<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">One of the new features in both Arduino Uno R4 boards is the inclusion of a single 12-bit DAC. This can generate discrete output voltages from 0 to 5 volts. It can also be used to generate waveforms, as our example here will illustrate.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This sketch will generate a sine wave or, rather, a \u201csimulated\u201d sine wave.\u00a0 You can control the frequency of the sine wave with a potentiometer.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Sine Wave Hookup<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">We will use an oscilloscope to view our sine wave, so the hookup is pretty simple. All we really need is a potentiometer, any linear-taper (if it doesn\u2019t specify a taper, it is probably linear) pot with a resistance of 5k or higher will work. I used a 10k potentiometer.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10173\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eDAC-Hookup.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eDAC-Hookup.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eDAC-Hookup.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">If you don\u2019t have access to a scope, you could send the output to an audio amplifier so that you could listen to the tones generated.\u00a0 If you choose to go this route, make sure your amplifier has a volume control and that it is down all the way when you first test everything!<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Sine Wave Code<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">This first example, as with all of the example code today, was installed when you installed the board manager for the Arduino Uno R4 boards.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">You can find this example, which is called \u201cSineWave,\u201d in the following location:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><i><span style=\"font-weight: 400;\">File\/Examples\/Examples for Arduino R4\u2026\/AnalogWave\/SineWave<\/span><\/i><\/li>\n<\/ul>\n<p><b>You may want to save the sketch under a different name, as it has an error in it that you will need to fix<\/b><span style=\"font-weight: 400;\">! More on that in a moment.<\/span><\/p>\n<p><b>Here is the Corrected Version<\/b><span style=\"font-weight: 400;\"> of the SineWave code:<\/span><\/p>\n<pre class=\"lang:default decode:true \" title=\"Corrected SineWave Sketch\">#include \"analogWave.h\"\r\n\r\nanalogWave wave(DAC);\r\n\r\nint freq = 10;  \/\/ in hertz, change accordingly\r\n\r\nvoid setup() {\r\n  Serial.begin(115200);\r\n  pinMode(A5, INPUT); \/\/ Fixed\r\n  wave.sine(freq);\r\n}\r\n\r\nvoid loop() {\r\n  freq = map(analogRead(A5), 0, 1024, 0, 10000); \/\/ Fixed\r\n  Serial.println(\"Frequency is now \" + String(freq) + \" hz\");\r\n  wave.freq(freq);\r\n  delay(1000);\r\n}<\/pre>\n<p><span style=\"font-weight: 400;\">The code is pretty simple, as it makes use of the \u201c<\/span><i><span style=\"font-weight: 400;\">analogWave<\/span><\/i><span style=\"font-weight: 400;\">\u201d library. You already have this library; it was installed with the board manager installation.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">After including the library, we create an object called \u201c<\/span><i><span style=\"font-weight: 400;\">wave<\/span><\/i><span style=\"font-weight: 400;\">\u201d and attach it to the DAC pin. The DAC pin is referenced by its built-in constant of \u201c<\/span><i><span style=\"font-weight: 400;\">DAC<\/span><\/i><span style=\"font-weight: 400;\">.\u201d<\/span><\/p>\n<p><span style=\"font-weight: 400;\">We also define an integer to hold the frequency.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Now we move to the Setup, where we need to correct our first error (there are actually two errors, the same one twice).<\/span><\/p>\n<p><span style=\"font-weight: 400;\">In Setup, we initialize the serial monitor. The next line is where the issue is.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The code has a <\/span><i><span style=\"font-weight: 400;\">pinMode<\/span><\/i><span style=\"font-weight: 400;\"> command, setting up pin A0 as an input. This is wrong, as A0 is the DAC output!\u00a0\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">A5 is the input from the potentiometer, and it really doesn\u2019t require a pinMode command as it\u2019s an analog input.\u00a0 So<\/span><b> you can either change \u201cA0\u201d to \u201cA5\u201d or just erase the whole line!<\/b><\/p>\n<p><span style=\"font-weight: 400;\">The next command defines the type of waveform we want to generate, as well as its frequency. As written, it will generate a sine wave, but you can change this if you wish. You have three choices:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">sine &#8211; Sine wave.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">square &#8211; Square wave.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">saw &#8211; Sawtooth wave.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Now on to the Loop!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The first thing we do is read the potentiometer and determine the frequency; it\u2019s all done in one line with a map and analogRead command. And, of course, this is where the other error is!<\/span><\/p>\n<p><b>Once again, A0 needs to be changed to A5<\/b><span style=\"font-weight: 400;\">.\u00a0 Had they defined a constant for this at the beginning of the sketch, you would have only needed to fix this in one place!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">After getting the pot value and converting it to a frequency value, we print the frequency to the serial monitor. Then, we call our wave object and generate a waveform as specified.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">We finish with a one-second delay, then repeat the Loop.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Sine Wave Demo<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Running the demo is as simple as loading the sketch to the Arduino Uno R4 Minima (or WiFi) board and observing the scope. You may have to adjust your scope settings.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10158\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-dac-demo.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-dac-demo.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-dac-demo.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">If you also observe the Serial Monitor, you\u2019ll see the frequency displayed, updated every second.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Turn the potentiometer and observe the waveform.\u00a0 You\u2019ll see how the frequency changes, with a maximum frequency of 10 kHz.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">When you look at the waveform, you\u2019ll see that it is actually a stepped approximation of a sine wave. Great for generating tones for a game or system alarm!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Experiment with the code by changing the type of generated wave, and observe the results on the scope.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Using the CAN Bus<\/span><\/h2>\n<p>Another feature of the new Arduino Uno R4 boards is the inclusion of a CAN Bus interface.<\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The Controller Area Network Bus, or CAN Bus, was originally created for the automotive industry to allow sensors and devices to easily &#8220;talk&#8221; to one another using a simple protocol.\u00a0 As it was created for automotive applications, it is electrically and physically robust, requiring low-cost components.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The CAN Bus is not limited to automotive applications; it can be used whenever you need to have microcontrollers exchange small amounts of information.\u00a0 It can be used over longer distances than I<\/span><span style=\"font-weight: 400;\">2<\/span><span style=\"font-weight: 400;\">C or SPI, and is also virtually immune to electrical noise when wired correctly with twisted pair wires and terminators.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10167\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-Bus-Topology.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-Bus-Topology.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-Bus-Topology.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Physically, the bus consists of two wires labeled CAN_HIGH and CAN_LOW.\u00a0 Each end of the bus has a termination resistor, usually 120 ohms.\u00a0 CAN Bus cables are twisted pairs, and the connectors often are DB(s.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The node of the CAN Bus are often called ECUs for Electronic Control Units. Each ECU can transmit to the bus, and every ECU receives all the traffic.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Each CAN Bus packet has an ID. When an ECU receives a data packet, it uses the ID to filter it. If the packet is filtered, it is ignored; only packets that make it through the filter are acted upon.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The bus itself is a differential design; this eliminates induced electrical noise as the amplitude of the noise on each line is equal and is thus canceled out.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">You can use the CAN Bus feature of the Arduino Uno R4 to join an existing CAN Bus (i.e. the one in your own vehicle) or to create a new network, which doesn\u2019t have to be for automotive use.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus Data Structure<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">CAN Bus data is packaged into a frame and can be broken down as illustrated in the following diagram:<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10161\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Data.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Data.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Data.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The elements of the frame are as follows:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Start of Frame (SOF)<\/b><span style=\"font-weight: 400;\"> &#8211; This is one bit set to \u201c0\u201d at the beginning of a frame.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Frame Identifier (ID)<\/b><span style=\"font-weight: 400;\"> &#8211; This is an identification bit used to determine who the frame is intended for. In the CAN 2.0A spec, this is 11 bits; in CAN 2.0B it is 29 bits).<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Remote Transmission Request (RTR)<\/b><span style=\"font-weight: 400;\"> &#8211; This is a single bit used to determine if this is a request to another ECU for data.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Control (CTRL)<\/b><span style=\"font-weight: 400;\"> &#8211; This is a six-bit sequence that has two components, the Identifier Extension Bit (IDE) and Data Length Code (DLC).<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Data<\/b><span style=\"font-weight: 400;\"> &#8211; This is the actual data we send, with a length of zero to 64 bits. Zero is a perfectly valid amount as if the frame is a request for data, it isn\u2019t likely that you will need to send data as well.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Cyclic Redundancy Check (CRC)<\/b><span style=\"font-weight: 400;\"> &#8211; This s a checksum to ensure the validity of the data. It is 16-bits long.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Acknowledgment (ACK)<\/b><span style=\"font-weight: 400;\"> &#8211; An acknowledgment that the node has received the data successfully.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>End of Frame (EOF)<\/b><span style=\"font-weight: 400;\"> &#8211; 7 bits signifying the end of the frame.<\/span><\/li>\n<\/ul>\n<p>The Arduino_CAN Library handles the logic for the CAN Bus<\/p>\n<h3><span style=\"font-weight: 400;\">Minima and WiFi CAN Bus Connections<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Oddly enough, although the Minima and WiFi boards have the same CAN Bus capabilities, they use different I\/O pins for their receive (CAN RX) and transmit (CAN TX) connections.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10166\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Wifi.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Wifi.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Wifi.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">On the Minima, the CAN Bus connection is as follows<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">CAN RX &#8211; Pin D5<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">CAN TX &#8211; Pin D4<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">And on the Arduino Uno R4 WiFi board, they are on different pins:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">CAN TX &#8211; Pin TX<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">CAN RX &#8211; PIN 13<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Naturally, you\u2019ll want to remember this when hooking up a CAN Bus Transceiver!<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus Transceiver<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">There are many CAN Bus Transceivers that you can use with the Arduino Uno R4 boards.\u00a0 One that I have had success with is the <\/span><a href=\"https:\/\/www.waveshare.com\/wiki\/SN65HVD230_CAN_Board\"><span style=\"font-weight: 400;\">Waveshare SN65HVD230<\/span><\/a><span style=\"font-weight: 400;\"> module, which is an inexpensive CAN Bus transceiver.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-weight: 400;\">One issue with this transceiver is that it operates on 3.3 volts, and <strong>although it can withstand being powered by a 5-volt power supply, <\/strong><\/span><strong><a href=\"https:\/\/www.waveshare.com\/w\/upload\/3\/3a\/SN65HVD230-CAN-Board-Datasheets.pdf\">the recommended supply voltage is between 3.0 and 3.6 volts<\/a><\/strong><span style=\"font-weight: 400;\"><strong>.<\/strong>\u00a0\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">So while you can operate this on 5 volts and save an additional component, I have decided to run mine on the recommended 3.3-volts and use a logic-level converter to handle the 3.3-volt to 5-volt logic-level differences.\u00a0<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10169\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-transceiver.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-transceiver.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-transceiver.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">This diagram shows the pinouts of both the WaveShare CAN Bus transceiver and a typical logic-level converter. Although a 4-channel converter is shown, you only require two channels, and you can use a different converter.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus Hookup<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Here is the hookup for the CAN Bus transceiver and the logic-level converter. As the pinouts for the CAN Bus are different between the Minima and WiFi boards, I have provided two hookup diagrams.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10165\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Hookup.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Hookup.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-Minima-Hookup.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10171\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-WiFi-Hookup.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-WiFi-Hookup.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eCAN-BUS-WiFi-Hookup.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">You will need to build two of these circuits for our experiment. You can use two of the same boards or \u201cmix and match\u201d them!<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus Code<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Once again, we will use code provided by Arduino for our experiment.\u00a0 Since we have two boards, we will need two sketches, one for the transmit side and the other for the receive.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">CANWrite<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The first sketch we will need is the one that transmits data, the <\/span><i><span style=\"font-weight: 400;\">CANWrite<\/span><\/i><span style=\"font-weight: 400;\"> sketch. This can be found in the Example sketches under <\/span><i><span style=\"font-weight: 400;\">Arduino_CAN<\/span><\/i><span style=\"font-weight: 400;\">, which is the name of the library used in the sketch.<\/span><\/p>\n<pre class=\"lang:default decode:true \" title=\"CANWrite\">\/**************************************************************************************\r\n * INCLUDE\r\n **************************************************************************************\/\r\n\r\n#include &lt;Arduino_CAN.h&gt;\r\n\r\n\/**************************************************************************************\r\n * CONSTANTS\r\n **************************************************************************************\/\r\n\r\nstatic uint32_t const CAN_ID = 0x20;\r\n\r\n\/**************************************************************************************\r\n * SETUP\/LOOP\r\n **************************************************************************************\/\r\n\r\nvoid setup()\r\n{\r\n  Serial.begin(115200);\r\n  while (!Serial) { }\r\n\r\n  if (!CAN.begin(CanBitRate::BR_250k))\r\n  {\r\n    Serial.println(\"CAN.begin(...) failed.\");\r\n    for (;;) {}\r\n  }\r\n}\r\n\r\nstatic uint32_t msg_cnt = 0;\r\n\r\nvoid loop()\r\n{\r\n  \/* Assemble a CAN message with the format of\r\n   * 0xCA 0xFE 0x00 0x00 [4 byte message counter]\r\n   *\/\r\n  uint8_t const msg_data[] = {0xCA,0xFE,0,0,0,0,0,0};\r\n  memcpy((void *)(msg_data + 4), &amp;msg_cnt, sizeof(msg_cnt));\r\n  CanMsg msg(CAN_ID, sizeof(msg_data), msg_data);\r\n\r\n  \/* Transmit the CAN message, capture and display an\r\n   * error core in case of failure.\r\n   *\/\r\n  if (int const rc = CAN.write(msg); rc &lt; 0)\r\n  {\r\n    Serial.print  (\"CAN.write(...) failed with error code \");\r\n    Serial.println(rc);\r\n    for (;;) { }\r\n  }\r\n\r\n  \/* Increase the message counter. *\/\r\n  msg_cnt++;\r\n\r\n  \/* Only send one message per second. *\/\r\n  delay(1000);\r\n}\r\n<\/pre>\n<p><span style=\"font-weight: 400;\">The sketch is pretty simple, as the Arduino_CAN library does most of the work.\u00a0\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">After including the library, we define an ID that will be used in the transmission.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">In Setup we start the Serial Monitor and the CAN Bus. The bus is run at 250 kBps.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">And in the Loop we compose a message and send it on the CAN Bus. After that, we increment the counter, add a one-second delay and then do it again.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">CANRead<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The second sketch is the one for the receive side.\u00a0 The <\/span><i><span style=\"font-weight: 400;\">CANRead<\/span><\/i><span style=\"font-weight: 400;\"> sketch, also included with the code samples, is a simple sketch that will do this nicely.<\/span><\/p>\n<pre class=\"lang:default decode:true \" title=\"CANRead\">\/**************************************************************************************\r\n * INCLUDE\r\n **************************************************************************************\/\r\n\r\n#include &lt;Arduino_CAN.h&gt;\r\n\r\n\/**************************************************************************************\r\n * SETUP\/LOOP\r\n **************************************************************************************\/\r\n\r\nvoid setup()\r\n{\r\n  Serial.begin(115200);\r\n  while (!Serial) { }\r\n\r\n  if (!CAN.begin(CanBitRate::BR_250k))\r\n  {\r\n    Serial.println(\"CAN.begin(...) failed.\");\r\n    for (;;) {}\r\n  }\r\n}\r\n\r\nvoid loop()\r\n{\r\n  if (CAN.available())\r\n  {\r\n    CanMsg const msg = CAN.read();\r\n    Serial.println(msg);\r\n  }\r\n}\r\n<\/pre>\n<p><span style=\"font-weight: 400;\">The beginning of the sketch is almost identical to the <\/span><i><span style=\"font-weight: 400;\">CANWrite<\/span><\/i><span style=\"font-weight: 400;\"> sketch; the only difference is that we don\u2019t need to define an ID.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">In the Loop, we simply read the incoming CAN Bus traffic for a message. If one is received, it is displayed on the Serial Monitor.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">CAN Bus Demo<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">To run the demonstration, you\u2019ll need to have two Arduino Uno R4 boards (Minima or WiFi) connected to CAN Bus transceivers, which in turn are connected together.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10182\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-minima-can-bus-demo.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-minima-can-bus-demo.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/uno-r4-minima-can-bus-demo.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">Load <\/span><i><span style=\"font-weight: 400;\">CANWrite<\/span><\/i><span style=\"font-weight: 400;\"> onto one of the boards and <\/span><i><span style=\"font-weight: 400;\">CANRead<\/span><\/i><span style=\"font-weight: 400;\"> onto another. You can open two instances of the Arduino IDE on one computer and use the two serial monitors to observe the results.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The CAN Bus itself can simply be two pieces of wire. If they are not too long, you won\u2019t require the 120-ohm terminator resistors.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If all is working, you should observe the CAN Bus data on the receive side, changing every second. Resetting the transmit side will restart the counter.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10157\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-can-bus-serial-monitors.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-can-bus-serial-monitors.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-can-bus-serial-monitors.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The transmit side Serial Monitor usually does not display anything unless the packets are not being received. Pull the USB cord out of the receive one temporarily to observe this message.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Although this is just a basic demonstration, it illustrates how simple it is to use the CAN Bus with the new Arduino Uno R4 boards.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Using the Arduino Uno R4 WiFi<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The Arduino Uno R4 WiFi boards bring the power of an ESP32 to the Arduino Uno.\u00a0\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The ESP32 S3 used in the Arduino Uno R4 WiFi can also be used independently, programmed using the ESP Header connector described earlier.\u00a0\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The ESP32 is also used when programming or communicating with the board. In normal operation, USB traffic is routed to the ESP32, which routes it to the Renesas RA4M1 via a \u201cbridge\u201d.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10177\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select1.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select1.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select1.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">If you decide to program the ESP32 independently, you will wipe its bootloader and will therefore need to connect directly to the Renesas RA4M1. This can be done in two ways.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10178\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select2.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select2.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select2.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The first method is to pull GPIO pin D40 on the RA4M1 HIGH.\u00a0 This essentially \u201cflips the switch\u201d and will cause traffic to be directly routed from the USB port to the RA4M1.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10179\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select3.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select3.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/RA4M1-ESP32-Select3.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The second method is to solder a jumper between the two \u201cRA4M1-UYSB\u201d jumper pads underneath the board.\u00a0 This also \u201cflips the switch\u201d.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">WiFi Access Point<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Of course, the reason many people will pick up the board is for its WiFi capabilities, and the new WiFiS3 library makes this very easy to use.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">There are several sample sketches included that will get you started with the WiFi.\u00a0 One that I ran in the video was to set up a WiFi Access Point.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">WiFi Access Point Code<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">You\u2019ll find this sketch in the Examples section under the WiFiS3 section, the <\/span><i><span style=\"font-weight: 400;\">AP_SimpleWebServer<\/span><\/i><span style=\"font-weight: 400;\"> example. As with many of the example sketches, this code is an adaptation of an earlier sketch, in this case, one written by Tom Igoe in 2012.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The purpose of this sketch is to create a WiFi Access point, which can then display a webpage. The webpage has two links, one to turn the built-in LED on and another to turn it off.<\/span><\/p>\n<pre class=\"lang:default decode:true \" title=\"AP_SimpleWebserver\">\/*\r\n  WiFi Web Server LED Blink\r\n\r\n  A simple web server that lets you blink an LED via the web.\r\n  This sketch will create a new access point (with no password).\r\n  It will then launch a new server and print out the IP address\r\n  to the Serial Monitor. From there, you can open that address in a web browser\r\n  to turn on and off the LED on pin 13.\r\n\r\n  If the IP address of your board is yourAddress:\r\n    http:\/\/yourAddress\/H turns the LED on\r\n    http:\/\/yourAddress\/L turns it off\r\n\r\n  created 25 Nov 2012\r\n  by Tom Igoe\r\n  adapted to WiFi AP by Adafruit\r\n *\/\r\n\r\n#include \"WiFiS3.h\"\r\n\r\n#include \"arduino_secrets.h\" \r\n\r\n\/\/\/\/\/\/\/please enter your sensitive data in the Secret tab\/arduino_secrets.h\r\nchar ssid[] = SECRET_SSID;        \/\/ your network SSID (name)\r\nchar pass[] = SECRET_PASS;        \/\/ your network password (use for WPA, or use as key for WEP)\r\nint keyIndex = 0;                 \/\/ your network key index number (needed only for WEP)\r\n\r\nint led =  LED_BUILTIN;\r\nint status = WL_IDLE_STATUS;\r\nWiFiServer server(80);\r\n\r\nvoid setup() {\r\n  \/\/Initialize serial and wait for port to open:\r\n  Serial.begin(9600);\r\n  while (!Serial) {\r\n    ; \/\/ wait for serial port to connect. Needed for native USB port only\r\n  }\r\n  Serial.println(\"Access Point Web Server\");\r\n\r\n  pinMode(led, OUTPUT);      \/\/ set the LED pin mode\r\n\r\n  \/\/ check for the WiFi module:\r\n  if (WiFi.status() == WL_NO_MODULE) {\r\n    Serial.println(\"Communication with WiFi module failed!\");\r\n    \/\/ don't continue\r\n    while (true);\r\n  }\r\n\r\n  String fv = WiFi.firmwareVersion();\r\n  if (fv &lt; WIFI_FIRMWARE_LATEST_VERSION) {\r\n    Serial.println(\"Please upgrade the firmware\");\r\n  }\r\n\r\n  \/\/ by default the local IP address will be 192.168.4.1\r\n  \/\/ you can override it with the following:\r\n  WiFi.config(IPAddress(192,48,56,2));\r\n\r\n  \/\/ print the network name (SSID);\r\n  Serial.print(\"Creating access point named: \");\r\n  Serial.println(ssid);\r\n\r\n  \/\/ Create open network. Change this line if you want to create an WEP network:\r\n  status = WiFi.beginAP(ssid, pass);\r\n  if (status != WL_AP_LISTENING) {\r\n    Serial.println(\"Creating access point failed\");\r\n    \/\/ don't continue\r\n    while (true);\r\n  }\r\n\r\n  \/\/ wait 10 seconds for connection:\r\n  delay(10000);\r\n\r\n  \/\/ start the web server on port 80\r\n  server.begin();\r\n\r\n  \/\/ you're connected now, so print out the status\r\n  printWiFiStatus();\r\n}\r\n\r\n\r\nvoid loop() {\r\n  \r\n  \/\/ compare the previous status to the current status\r\n  if (status != WiFi.status()) {\r\n    \/\/ it has changed update the variable\r\n    status = WiFi.status();\r\n\r\n    if (status == WL_AP_CONNECTED) {\r\n      \/\/ a device has connected to the AP\r\n      Serial.println(\"Device connected to AP\");\r\n    } else {\r\n      \/\/ a device has disconnected from the AP, and we are back in listening mode\r\n      Serial.println(\"Device disconnected from AP\");\r\n    }\r\n  }\r\n  \r\n  WiFiClient client = server.available();   \/\/ listen for incoming clients\r\n\r\n  if (client) {                             \/\/ if you get a client,\r\n    Serial.println(\"new client\");           \/\/ print a message out the serial port\r\n    String currentLine = \"\";                \/\/ make a String to hold incoming data from the client\r\n    while (client.connected()) {            \/\/ loop while the client's connected\r\n      delayMicroseconds(10);                \/\/ This is required for the Arduino Nano RP2040 Connect - otherwise it will loop so fast that SPI will never be served.\r\n      if (client.available()) {             \/\/ if there's bytes to read from the client,\r\n        char c = client.read();             \/\/ read a byte, then\r\n        Serial.write(c);                    \/\/ print it out to the serial monitor\r\n        if (c == '\\n') {                    \/\/ if the byte is a newline character\r\n\r\n          \/\/ if the current line is blank, you got two newline characters in a row.\r\n          \/\/ that's the end of the client HTTP request, so send a response:\r\n          if (currentLine.length() == 0) {\r\n            \/\/ HTTP headers always start with a response code (e.g. HTTP\/1.1 200 OK)\r\n            \/\/ and a content-type so the client knows what's coming, then a blank line:\r\n            client.println(\"HTTP\/1.1 200 OK\");\r\n            client.println(\"Content-type:text\/html\");\r\n            client.println();\r\n\r\n            \/\/ the content of the HTTP response follows the header:\r\n            client.print(\"&lt;p style=\\\"font-size:7vw;\\\"&gt;Click &lt;a href=\\\"\/H\\\"&gt;here&lt;\/a&gt; turn the LED on&lt;br&gt;&lt;\/p&gt;\");\r\n            client.print(\"&lt;p style=\\\"font-size:7vw;\\\"&gt;Click &lt;a href=\\\"\/L\\\"&gt;here&lt;\/a&gt; turn the LED off&lt;br&gt;&lt;\/p&gt;\");\r\n\r\n            \/\/ The HTTP response ends with another blank line:\r\n            client.println();\r\n            \/\/ break out of the while loop:\r\n            break;\r\n          }\r\n          else {      \/\/ if you got a newline, then clear currentLine:\r\n            currentLine = \"\";\r\n          }\r\n        }\r\n        else if (c != '\\r') {    \/\/ if you got anything else but a carriage return character,\r\n          currentLine += c;      \/\/ add it to the end of the currentLine\r\n        }\r\n\r\n        \/\/ Check to see if the client request was \"GET \/H\" or \"GET \/L\":\r\n        if (currentLine.endsWith(\"GET \/H\")) {\r\n          digitalWrite(led, HIGH);               \/\/ GET \/H turns the LED on\r\n        }\r\n        if (currentLine.endsWith(\"GET \/L\")) {\r\n          digitalWrite(led, LOW);                \/\/ GET \/L turns the LED off\r\n        }\r\n      }\r\n    }\r\n    \/\/ close the connection:\r\n    client.stop();\r\n    Serial.println(\"client disconnected\");\r\n  }\r\n}\r\n\r\nvoid printWiFiStatus() {\r\n  \/\/ print the SSID of the network you're attached to:\r\n  Serial.print(\"SSID: \");\r\n  Serial.println(WiFi.SSID());\r\n\r\n  \/\/ print your WiFi shield's IP address:\r\n  IPAddress ip = WiFi.localIP();\r\n  Serial.print(\"IP Address: \");\r\n  Serial.println(ip);\r\n\r\n  \/\/ print where to go in a browser:\r\n  Serial.print(\"To see this page in action, open a browser to http:\/\/\");\r\n  Serial.println(ip);\r\n\r\n}\r\n<\/pre>\n<p><span style=\"font-weight: 400;\">As with all the example sketches, this one includes an &#8220;arduino_secrets.h&#8221; file. The purpose of this file, with most of the sketches, is to hold your WiFi credentials (SSID and password), but on this sketch, it serves a different purpose. With this sketch, the &#8220;arduino_secrets.h&#8221; file holds the SSID and password for the Access Point you&#8217;re setting up. You can leave it as it is or change it.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The code is a bit long, but essentially it establishes an access point and then looks for a client connection. When it sees one, it monitors the URL returned when a client clicks one of the links. It then uses the URL address to determine which link has been activated and sets the LED accordingly.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-weight: 400;\">No hookup is required to test this sketch out, although you can tie an LED with a dropping resistor (remember, 470 ohms or higher) onto pin D13 to observe the results.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">WiFi Access Point Demo<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Load the sketch and then go to a phone, tablet, or computer with WiFi capabilities. Open the WiFi settings and look for your access point network; if you didn&#8217;t edit &#8220;arduino_secrets.h,&#8221; then the SSID will be &#8220;testAP&#8221; and the password will be &#8220;123456789&#8221;.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">After you connect to the access point, open a web browser at the IP address specified in the sketch. If you didn\u2019t edit line 56, then it should be 192.48.56.2.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10159\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-wifi-ap-demo.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-wifi-ap-demo.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-uno-r4-wifi-ap-demo.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">You should see a web page with very large text and two links. Clicking the links should control the built-in LED on the Arduino Uno R4 WiFi board.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Try out a few of the other sample sketches in the WiFiS3 section to get a feel for how to program WiFi applications on your new Arduino Uno R4 WiFi board.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">LED Matrix<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Probably the most distinguishing feature of the new Arduino Uno R4 WiFi board is the 12&#215;8 LED matrix that occupies about a third of the board&#8217;s real estate.\u00a0 It\u2019s an interesting and unexpected addition, in fact, when Arduino was initially easing about the release of the new board, they covered the LED matrix up, so we couldn\u2019t see it!<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">LED Matrix Wiring<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">The LED Matrix consists of 96 LEDs controlled by only 11 GPIO pins. To accomplish this, a technique called \u201cCharlieplexing\u201d was used in the design.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10174\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Charlieplex.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Charlieplex.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Charlieplex.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The Charlieplexing technique was developed by Charles &#8220;Charlie&#8221; M. Allen, an applications engineer at Maxim Electronics. It takes advantage of there being three states in a microcontroller&#8217;s digital output lines:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">HIGH<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">LOW<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">HIGH-Z (High Impedance)<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">That third state is achieved by turning the I\/O pin into an input.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Given these three states, you can control multiple LEDs by arranging them in groups of two, wired in reverse polarity.\u00a0 In fact, with 11 I\/O pins, you can actually control 110 LEDs!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">You can address the LEDs individually; they are numbered as illustrated in the following diagram:<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10175\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Layout.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Layout.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eLED-Matrix-Layout.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<h3><span style=\"font-weight: 400;\">LED Matrix Sample Code<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">In the example sketches, you\u2019ll find several different code samples that you can use to try out the LED matrix.<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Display Single Frame<\/b><span style=\"font-weight: 400;\"> &#8211; Loads individual frames. You can exchange the included data with your own data<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Game of Life<\/b><span style=\"font-weight: 400;\"> &#8211; A cellular automaton devised by the British mathematician John Horton Conway in 1970.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Matrix Frame Buffer<\/b><span style=\"font-weight: 400;\"> &#8211; Illustrates how to compose a frame and then alter its contents<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Play Animation<\/b><span style=\"font-weight: 400;\"> &#8211; Illustrates how to do animation with multiple frames.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">You\u2019ll also find the<\/span><i><span style=\"font-weight: 400;\"> PlayAnimation<\/span><\/i><span style=\"font-weight: 400;\"> sketch as well, this is the sketch initially loaded onto the Arduino Uno R4 WiFi boards when they are shipped from the factory.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">LED Matrix Editor<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Arduino has provided a tool that allows you to create patterns on the LED matrix, patterns that you can then download to use in your own code.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">All you need to do to use this tool is to load a sketch onto your Arduino Uno R4 WiFi board. You keep the board connected to the computer, make sure no other instances of the Serial Monitor are running, and go to the Arduino LED Matrix Editing tool and connect to your computer.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The matrix editor will then use your USB port to communicate to the Arduino board, setting it\u2019s LED matrix.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">LivePreview Sketch<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">The first step is to install the <\/span><i><span style=\"font-weight: 400;\">LivePreview <\/span><\/i><span style=\"font-weight: 400;\">sketch onto your Arduino Uno R4 WiFi board.\u00a0 You\u2019ll find this sketch among the other LED Matrix example sketches.<\/span><\/p>\n<pre class=\"lang:default decode:true \" title=\"LivePreview\">\/*\r\n  This sketch allows live editing of the matrix pixels using WebSerial\r\n  To test, head to https:\/\/ledmatrix-editor.arduino.cc\r\n  press 'p' and select 'UNO R4 WiFi' board from the list.\r\n\r\n  Don't forget to close any serial monitor already opened.\r\n*\/\r\n\r\n#include \"Arduino_LED_Matrix.h\"\r\n\r\nArduinoLEDMatrix matrix;\r\n\r\nvoid setup() {\r\n  Serial.begin(115200);\r\n  matrix.begin();\r\n}\r\n\r\nuint32_t frame[] = {\r\n  0, 0, 0, 0xFFFF\r\n};\r\n\r\nvoid loop() {\r\n  if(Serial.available() &gt;= 12){\r\n    frame[0] = Serial.read() | Serial.read() &lt;&lt; 8 | Serial.read() &lt;&lt; 16 | Serial.read() &lt;&lt; 24;\r\n    frame[1] = Serial.read() | Serial.read() &lt;&lt; 8 | Serial.read() &lt;&lt; 16 | Serial.read() &lt;&lt; 24;\r\n    frame[2] = Serial.read() | Serial.read() &lt;&lt; 8 | Serial.read() &lt;&lt; 16 | Serial.read() &lt;&lt; 24;\r\n    matrix.loadFrame(frame);\r\n  }\r\n}\r\n\r\n<\/pre>\n<p><span style=\"font-weight: 400;\">The sketch uses the new <\/span><i><span style=\"font-weight: 400;\">ArduinoLEDMatrix<\/span><\/i><span style=\"font-weight: 400;\"> library and is very simple. It sets up the serial port and a matrix object that represents a frame of the display. It then goes into the Loop, where it monitors the serial monitor port and captures its data to fill the frame object. The object is then written to the display.<\/span><\/p>\n<h4><span style=\"font-weight: 400;\">LED Matrix Editor Website<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">After you have loaded the sketch onto the Arduino Uno R4 WiFi board, head over to the <\/span><a href=\"https:\/\/ledmatrix-editor.arduino.cc\/\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino LED Matrix Editor<\/span><\/a><span style=\"font-weight: 400;\">. I recommend using Google Chrome for this, as some other browsers don\u2019t work properly with the editor.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">When you arrive at the page, you will be prompted to allow the site to interact with your computer. Allow this, as it is essential for the product to work.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Now click the icon on the top of the page. A dialog box will open, explaining that you are about to connect to your computer.\u00a0 Follow the steps, and you will come to a page listing the serial devices on your system. Select the one with the Arduino Uno R4 WiFi board and allow connections to it.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">And now the fun begins!\u00a0 Try clicking on the boxes in the editor, while observing the LED matrix on the Arduino board. You should see the pattern you draw on the screen replicated on the display.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10154\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-1.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-1.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-1.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The download button allows you to download a ZIP file with the frame code for the display you have drawn. You can then use this code with the Display Single Frame sketch.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">You can also save and download multiple frames to try with the Play Animation example sketch.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10155\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-2.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-2.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/arduino-led-matrix-editor-2.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">I think it\u2019s great that Arduino has provided this tool, as it will make designing cool LED matrix displays a lot easier!<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Uno R4 vs. Uno R3<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">To finish things off, I wanted to compare the performance of the new Arduino Uno boards against their predecessors.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">I also decided to throw in a few other popular microcontrollers to get a \u201cballpark\u201d figure to see where the new Arduino\u2019s stand in terms of performance.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Of course, benchmark tests don\u2019t precisely simulate \u201creal-life\u201d situations and should be treated as just one element in evaluating a microcontroller.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Benchmarking Setup<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Finding a benchmark program that would run on all the microcontrollers I selected proved to be a bit of a challenge. I finally settled on the <\/span><a href=\"https:\/\/github.com\/ghalfacree\/Arduino-Sketches\/tree\/master\/Dhrystone\/dhry21a\"><span style=\"font-weight: 400;\">Dhrystone Benchmark Sketch<\/span><\/a><span style=\"font-weight: 400;\">, an older program that has been recompiled to use with microcontrollers.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">However, the sketch wasn\u2019t perfect, as it doesn\u2019t run long enough to test some more modern microcontrollers. It can be fixed, though, by increasing the number of iterations that it runs through. By default, it goes through 300,000 iterations, but for the most powerful microcontroller I tested (the Arduino Giga R1), I had to bump that up to 5 million iterations!<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">Test Results<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">Here are the RAW results for the benchmarks:<\/span><\/p>\n<p><b>Arduino Uno R3:<\/b><\/p>\n<p><b>300000 runs<\/b><span style=\"font-weight: 400;\"> through Dhrystone<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Microseconds for one run through Dhrystone: 57.78<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dhrystones per Second: 17306.53<\/span><\/p>\n<p><span style=\"font-weight: 400;\">VAX MIPS rating = 9.85<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>Arduino Uno R4<\/b><\/p>\n<p><b>300000 runs<\/b><span style=\"font-weight: 400;\"> through Dhrystone<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Microseconds for one run through Dhrystone: 16.04<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dhrystones per Second: 62333.22<\/span><\/p>\n<p><span style=\"font-weight: 400;\">VAX MIPS rating = 35.48<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>ESP32-S2<\/b><\/p>\n<p><b>900000 runs <\/b><span style=\"font-weight: 400;\">through Dhrystone<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Microseconds for one run through Dhrystone: 3.83<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dhrystones per Second: 260998.10<\/span><\/p>\n<p><span style=\"font-weight: 400;\">VAX MIPS rating = 148.55<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>ESP32-PICO<\/b><\/p>\n<p><b>900000<\/b> <b>runs<\/b><span style=\"font-weight: 400;\"> through Dhrystone<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Microseconds for one run through Dhrystone: 3.18<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dhrystones per Second: 314080.44<\/span><\/p>\n<p><span style=\"font-weight: 400;\">VAX MIPS rating = 178.76<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><b>Arduino Giga R1<\/b><\/p>\n<p><b>5000000 runs<\/b><span style=\"font-weight: 400;\"> through Dhrystone<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Microseconds for one run through Dhrystone: 0.64<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Dhrystones per Second: 1567465.44<\/span><\/p>\n<p><span style=\"font-weight: 400;\">VAX MIPS rating = 892.13<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"font-weight: 400;\">And here is a chart summarizing those results.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-10160\" src=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eBenchmark.jpg?resize=750%2C422&#038;ssl=1\" alt=\"\" width=\"750\" height=\"422\" srcset=\"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eBenchmark.jpg?w=768&amp;ssl=1 768w, https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eBenchmark.jpg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"(max-width: 750px) 100vw, 750px\" data-recalc-dims=\"1\" \/><\/p>\n<p><span style=\"font-weight: 400;\">The tests show that the new Arduino Uno R4 board is about four times as powerful as the original R3 board.\u00a0 The ESP32 boards were almost four times as powerful as the new Uno R4 boards, which was not surprising considering their clock speed.\u00a0 And the Arduino Giga R1 is a monster, nearly 100 times more powerful than the original Uno R3.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Again, I wouldn\u2019t get too hung up on benchmark results, but it does show that you should expect a substantial performance improvement when upgrading an older Uno R3 design with a new Arduino Uno R4.<\/span><\/p>\n<h2><span style=\"font-weight: 400;\">Conclusion<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The new Arduino Uno R4 boards are an improvement over the older Arduino Uno R3 boards. They are faster, have more memory, and sport many intriguing features. The USB-C port is a welcome update from the older type-A port. Including CAN Bus connectivity and a DAC will inspire many exciting applications and projects.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">You need to keep the 8mA pin current limitation in mind when porting older designs to this board, but it shouldn\u2019t be much of an issue, except for driving LEDs directly.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The price of both boards is reasonable, although WiFi-enabled microcontrollers like the Pico W and ESP32 are available for less. However, those boards are smaller, circuit board-mounted designs, whereas the Uno is a stand-alone board made for experimenters.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">For experimenters, students, and those working with CAN Bus, these boards are a bargain and are certainly an exciting addition to the Arduino family.<\/span><\/p>\n<p>&nbsp;<\/p>\n<div class=\"dbwspartsbox\">\n<h3>Parts List<\/h3>\n<p><em>Here are some components that you might need to complete the experiments in this article. Please note that some of these links may be affiliate links, and the DroneBot Workshop may receive a commission on your purchases. This does not increase the cost to you and is a method of supporting this ad-free website.<\/em><\/p>\n<p>Arduino Uno R4 Minina &#8211; <a href=\"https:\/\/store.arduino.cc\/products\/uno-r4-minima\" target=\"_blank\" rel=\"noopener\">Arduino Store<\/a><\/p>\n<p>Arduino Uno R4 WiFi &#8211; <a href=\"https:\/\/store.arduino.cc\/products\/uno-r4-wifi\" target=\"_blank\" rel=\"noopener\">Arduino Store<\/a><\/p>\n<p>Waveshare SN65HVD230 &#8211; <a href=\"https:\/\/amzn.to\/3OAWf3M\" target=\"_blank\" rel=\"noopener\">Amazon<\/a><\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<div class=\"dbwsresourcebox\">\n<h3><span style=\"font-weight: 400;\">Resources<\/span><\/h3>\n<p><a href=\"https:\/\/docs.arduino.cc\/hardware\/uno-r4-wifi\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 Wifi<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Arduino main page for WiFi board.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-wifi\/cheat-sheet\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 WiFi Cheat Sheet<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; An Arduino page linking to multiple WiFi board resources.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/static\/7f708a58b837c423dbc63bb66bac0515\/ABX00087-datasheet.pdf\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 WiFi Datasheet<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Official datasheet from Arduino (PDF Document).<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/hardware\/uno-r4-minima\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 Minima<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Arduino main page for Minima board.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-minima\/cheat-sheet\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 Minima Cheat Sheet<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; An Arduino page linking to multiple Minima board resources.\u00a0<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/resources\/datasheets\/ABX00080-datasheet.pdf\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 Minima Datasheet<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Official datasheet from Arduino (PDF Document).<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-minima\/dac\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino DAC Guide<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Guide to the 12-bit DAC on the Minima and WiFi boards.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-wifi\/led-matrix\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino LED Matrix Guide<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Guide to the 12 x 8 LED Matrix on the Arduino Uno R4 WiFi board.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-minima\/can\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino CAN Bus Guide<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Guide to the CAN Bus on the Arduino Uno R4 Minima &#8211; also applies to WiFi with pin changes.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-minima\/usb-hid\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino USB HID Guide<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Guide to using the USB connector in Human Interface Device mode.<\/span><\/p>\n<p><a href=\"https:\/\/docs.arduino.cc\/tutorials\/uno-r4-wifi\/wifi-examples\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino WiFi Network Examples<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; Code examples for the Arduino Uno R4 WiFi board.<\/span><\/p>\n<p>&nbsp;<\/p>\n<p><a href=\"https:\/\/forum.arduino.cc\/t\/radio-module-firmware-version-0-2-0-is-now-available\/1147361\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Arduino Uno R4 WiFi Firmware Update<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; (Instructions for updating the firmware in the Arduino Uno R4 WiFi. Thai update resolves issues with Bluetooth and joining the Arduino IoT Cloud.<\/span><\/p>\n<p><a href=\"https:\/\/github.com\/ghalfacree\/Arduino-Sketches\/tree\/master\/Dhrystone\/dhry21a\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Dhrystone Benchmark Sketch<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; The sketch which I used to obtain the benchmark figures.<\/span><\/p>\n<p><a href=\"https:\/\/www.digikey.ca\/en\/resources\/conversion-calculators\/conversion-calculator-led-series-resistor\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">DigiKey LED Calculator<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; An online utility to determine the resistance of an LED dropping resistor. Great for keeping the current draw under 8 mA.<\/span><\/p>\n<p><a href=\"https:\/\/www.waveshare.com\/wiki\/SN65HVD230_CAN_Board\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">WaveShare SN65HVD230 Wiki<\/span><\/a><span style=\"font-weight: 400;\"> &#8211; More info regarding the CAN Bus transceiver.<\/span><\/p>\n<\/div>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>After 12 years, Arduino has released the latest edition of the classic Arduino Uno. Actually, it&#8217;s two boards, the Arduino Uno R4 Minima and the Arduino Uno R4 WiFi.<\/p>\n<p>These boards are 5-volt logic devices and are physically compatible with the older Arduino Uno R3 boards, preserving your investment in shields and prototyping equipment. In addition, they offer many new features, several of which we&#8217;ll examine today.<\/p>\n","protected":false},"author":1,"featured_media":10128,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[9,90],"tags":[44],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/i0.wp.com\/dronebotworkshop.com\/wp-content\/uploads\/2023\/07\/\u200eArduino-Uno-R4-Boards.jpg?fit=768%2C432&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p74ClK-2Dl","jetpack-related-posts":[],"_links":{"self":[{"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/posts\/10127"}],"collection":[{"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/comments?post=10127"}],"version-history":[{"count":17,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/posts\/10127\/revisions"}],"predecessor-version":[{"id":10241,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/posts\/10127\/revisions\/10241"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/media\/10128"}],"wp:attachment":[{"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/media?parent=10127"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/categories?post=10127"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dronebotworkshop.com\/wp-json\/wp\/v2\/tags?post=10127"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}