Hi guys, I accidentally burned the RA4M1 chip on my UNO R4 WiFi board by shorting the +5V and VIN pins. I had to transfer the chip from the UNO R4 Minima board, and now the IDE detects the board as Minima.
Is there a way to reflash the chip so that it is detected as belonging to the WiFi board?
Or, if I don't use the ESP32 chip, can I just ignore the formal name?
Hi @herz_tau, I think the problem will be solved by the following procedure:
- Selecting Tools > Board > Arduino UNO R4 Boards > Arduino UNO R4 WiFi from the Arduino IDE menus.
- Upload any sketch to the UNO R4 WiFi board.
After that, the board should be identified as "Arduino UNO R4 WiFi".
Thank you, but no - it doesn't work out that easy. If I just select UNO R4 WiFi instead of UNO R4 Minima, the device is not recognized:
Cannot perform port reset: TOUCH: error during reset: opening port at 1200bps: Invalid serial port
No device found on COM13
Failed uploading: uploading error: exit status 1
If I'm telling the truth, then the sketch is compiled and uploaded. 
I think you will need to flash the WiFi bootloader to it.
The idea is logical, this procedure is not as trivial as in the case of "traditional" Arduino boards based on the AVR platform.
Does anyone have step-by-step instructions?
I think I've tried all the options, including Run espflash directly, as well as attempts to rewrite the bootloader using RFP from Renesas.
I also used a short circuit between the MD and GND pins to put the MCU into DFU mode,
I followed this. Nothing helped. After these procedures, the board is no longer recognized as either R4 WIFI or R4 Minima. I managed to roll it back to Minima with difficulty.
Hmmm, I'm not sure why you thread jacked the thread I started which was for assistance with some custom hardware using a different variant of the RA4M1 chip than is used in the R4 Uno.
Your problem is simply how to flash the correct bootloader. My request was for assistance on how to port the bootloader and subsequent Arduino sketches/programmes to recognise the different pin outs etc.
You'll get better community engagement and help in your own subject specific thread.
Perhaps you are right. I would be glad if the moderator could unlink my posts and separate them into a new topic.
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I have now done as requested. Carry on.
Regards, pert
Thanks!
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Try this:
- Unplug the USB cable of the UNO R4 WiFi board from your computer.
- Connect the UNO R4 WiFi board to your computer with the USB cable.
- Press and release the button marked "RESET" on your UNO R4 WiFi board quickly twice.
You should now see the on-board LED that is marked "L" start pulsing. - Select the port of the UNO R4 WiFi board from Arduino IDE's Tools > Port menu.
The double reset you performed in step (3) can cause the port number of the board to change, so don't assume you already have the correct port selected. - Select Sketch > Upload from the Arduino IDE menus (or click the "Upload" button).
The upload should now complete successfully.
Thank you very much. I have already tried this too in the past.
First, the "L" LED on the WIFI board does not respond to double pressing the "RESET" button. Apparently because on the MINIMA board it was connected to pin P111, and on the WIFI board - to pin P102. But that's not the main thing. The main thing is that before double-clicking the RESET button, the board was detected on the COM13 port:
After such a double click the port disappears completely:
And, of course, it becomes impossible to upload any sketch.
A port with a different number appears if I short the MD pin (#1 on the JANALOG connector) to ground:
But even in this case, the sketch does not upload and an error message appears:
Sketch uses 58332 bytes (22%) of program storage space. Maximum is 262144 bytes.
Global variables use 6984 bytes (21%) of dynamic memory, leaving 25784 bytes for local variables. Maximum is 32768 bytes.
No device found on COM17
Failed uploading: uploading error: exit status 1