Uno R4 board discussion

Official Hardware UNO Family UNO R4 Minima
1

If I could only hand testing my Uno 4u board over to someone with a Uno R4....

2

I've got a Uno 4u and an Uno R4...
Tell me what tests you want done.

3

Speed tests,
In the calculation department and the pin control department.

4

I was going to use a screen for the pin control speed tests....

5

We are off topic here, maybe lets move this to a dedicated topic?

6

It was in topic till someone suggested helping. :melting_face:

7

Well lets go over specifics in a new thread, also could a @moderators split this thread for us please?

8

Done as requested.

9

I will post an "on paper" comparison between the two MCUs.

10
Specification UNO R4 – Minima VS UNO 4U VS UNO R3
Microcontroller RA4M1 (Arm Cortex®-M4), :arrow_left:︎4X AVR128DA28 (Microchip AVR®) :arrow_left:︎1X ATmega328P,
32-bit Processor 8-bit Processor 8-bit Processor
Clock Speed 48 MHz :arrow_left:︎2X 24 MHz :arrow_left:︎1.5X 16 MHz
USB-Connector USB-C :arrow_left:︎ USB-B :heavy_equals_sign: USB-B
Pins -14 digital I/O :arrow_right:︎ -16 digital I/O :arrow_left:︎ -14 digital I/O
-6 PWM :arrow_right:︎ -13 PWM :arrow_left:︎ -6 PWM
-6 analog input :arrow_right:︎ -10 analog input :arrow_left:︎ -6 analog input
-1 analog output (DAC) :heavy_equals_sign: -1 analog output (DAC) :arrow_left:︎ -0 analog output (DAC)
~14 External Interrupts :arrow_right:︎ -22 External Interrupts :arrow_left:︎ -2 External Interrupts
Connectors Serial Wire Debug (SWD), ICSP Universal Programming and Debug Interface(UPDI), ICSP ICSP
Communication UART 1 Native & 1 on TX/RX Pins, I2C, SPI, CAN :arrow_left:︎ 3x UART, I2C, 2x SPI :arrow_left:︎ UART, I2C, SPI
Power -I/O Voltage 5V :arrow_right:︎ -I/O Voltage 5V or 3.3V :arrow_left:︎ -I/O Voltage 5V
-Input voltage (nominal) 6-24V :arrow_left:︎ -Input Voltage (recommended) 7-12V, (limit) 6-20V :arrow_left:︎ -Input Voltage (recommended) 7-12V, (limit) 6-20V
-Power Supply Connector Barrel Jack :heavy_equals_sign: -Power Supply Connector Barrel Jack :heavy_equals_sign: -Power Supply Connector Barrel Jack
-DC Current per I/O Pin 8 mA :arrow_right:︎ -DC Current per I/O Pin 50 mA :arrow_left:︎ -DC Current per I/O Pin 20 mA
Flash Memory 256 kB, 8 kB data :arrow_left:︎2X 128 kB :arrow_left:︎4X 32 kB
SRAM 32 kB :arrow_left:︎2X 16 kB :arrow_left:︎8X 2 kB
EEPROM 8 kB :arrow_left:︎16X 0.5 kB :arrow_right:︎ 2X 1 kB
Dimensions Width 53.4 mm, Length 68.6 mm :heavy_equals_sign: Width 53.4 mm, Length 68.6 mm :heavy_equals_sign: Width 53.4 mm, Length 68.6 mm
Points 7.5 points 10 points 1 point
11

For each thing better (indicated by this symbol :arrow_left: or green highlight) is have awarded one point.

However for the 32-bit processor and EEPROM I have only awarded quarter a point since it depends on who you are which is better (indicated by yellow highlight).
Also for something that is slightly better (indicated by this symbol :arrow_right: or blue highlight) is awarded half a point.

12

We see that on paper the Uno 4u wins due to more I/O functionality.

I have not included the AVR128DA28's ZCDs(Zero Cross Detectors), CCL(Custom Configurable Logic), Event System channels, ACs(Analog Comparators) and the hardware timers in this comparison.

The Uno R4's Mouse/Keyboard Emulation (HID), RTC(Real-Time Clock), OPAMP(Operational Amplifier), MPU(Memory Protection Unit) and FPU(Floating Point Unit) are not included in this comparison either.

13

Your choice of highlight colours seems terrible; I have to highlight it on my PC to be able to see what the highlighted text is.

14

That is true.
I will have to research more about what colours are available.

15

That seems quite unlikely. You seem to be comparing "absolute max" ratings from the AVR-DA with "recommended" maximums on the mega328p (which has a "absolute max" of 40mA in datasheet.)
If your comparison is to be at all useful, you need to be more careful.

However for the 32-bit processor ... it depends on who you are which is better

How do you figure? I mean, you've also left out a whole bunch of features that the R4 has than 8bit chips don't even attempt (they may or may not be relevant to the Arduino environment, but still...)

Yeah, I sort-of wish that "Uno R4" had a new AVR (DA or DB) rather than the ARM chip, but ... you seem determined to have the 4u come out ahead...

16

It is meant to say absolute maximum.

17

I have listed all the things I have left out, well not all of them.
Also I need to change the scoring method so 32 bit and higher clock speeds are scored higher.
Some people prefer 8-bit.....Its more "challenging".

18

Here is a more complete list of features the Uno R4 has:
(Taken from the chips documentation since it isn't mentioned by Arduino.)

  1. 2x UART (one UART is "apparently" used by the USB-C plug).
  2. 2x SPI (I have no idea what pins the other SPI is mapped too).
  3. 1x CAN bus.
  4. 2x I2C.
  5. 1x 14-bit ADC.
  6. 1x 12-bit DAC.
  7. 3x OPAMPS.
  8. 2x Analog Comparators.
  9. 2x 8-bit DACs.
  10. 2x 32-bit General PWM Timers.
  11. 6x 16-bit General PWM Timers.
  12. 2x Low Power Asynchronous General-Purpose Timer.
  13. Watch Dog Timer.
  14. Real Time Clock.
  15. 4x DMA Controllers.
  16. Event Link Controller.
  17. Data Transfer Controller.
  18. Key Interrupt Controller.
  19. Power-on Reset.
  20. Low Voltage Detection.
  21. Security/Encryption covering: AES128/256, GHASH and True Random Number Generator.
  22. Segment LCD Controller (4 com × 21 seg or 8 com × 17 seg).
  23. Capacitive Touch Sensing Unit.
  24. Multiple clock sources, this is normal.....I am not listing them.
  25. 49x General Purpose I/O Ports.
  26. A lot of safety features that are unnecessary to use.

Where all these features disappeared to I have no idea, perhaps the current Arduino software doesn't support it.

The maximum current that can be sourced in total to every pin is 60mA.

19

Here is a more complete list of the features the AVR128DA28 has:
(They are all more or less supported by the current software core.)

  1. 3x UART.
  2. 2x SPI.
  3. 1x I2C.
  4. 1x 12-bit ADC.
  5. 1x 10-bit DAC.
  6. 3x Analog Comparators.
  7. 2x 16-bit Timer Type A.
  8. 3x 16-bit Timer Type B.
  9. 1x 12-bit Timer Type D.
  10. 1x 16-bit Real Time Counter. (It isn't a Real Time Clock.)
  11. Watch Dog Timer.
  12. 1x Zero Cross Detectors.
  13. 4x Custom Logic Blocks.
  14. 8x Event System Channels.
  15. Peripheral Touch Controller.
  16. Multiple clock sources, this is normal.....I am not listing them.
  17. 22x General Purpose I/O Pins.

The maximum current draw from any standard I/O pin is 50mA.

20

As for the current draw from any pin, I will recommend that 15mA is a "safe" amount to draw based on the datasheet.
The datasheet doesn't actually state a safe current draw. :expressionless: