Feather M4 CAN Express Not Sending Messages Moderators: adafruit_support_bill, adafruit

[owenp]

I'm working with the Feather M4 CAN Express and FeatherWing 128x64 OLED Adafruit boards. The OLED boards are used for displaying and configuring CAN messages using the buttons on the board. In total, I've ordered 35 of these boards each (I will need this many for this specific use case) and 7 of the CAN boards are not sending CAN messages. All of the boards were soldered, code uploaded, and tested the same way which is why it's confusing these 7 don't work. For information, I'm using a IXXAT CAN interface to view the CAN messages.

I've tried uploading the example 'CANSending' code and updating the bootloader on the boards. Neither of these options have worked.

I'm beginning to think these boards are faulty but this is a very high failure rate so please let me know any other possible solutions. As mentioned before, I will need these boards to be working and don't want to order any more if they also do not work.

[mikeysklar]

Can you post photos top and bottom of a non-working board (one of the seven) and the same for a working board? Maybe there is a clue in a component change or PCB identifier?

[owenp]

Update: Using another example code, a colleague found out that these boards failed the CAN initialization. What typically causes a board to fail CAN initialization?

Also here are the pictures, apologies for the bad quality, my phone would not focus at all.
Board that isn't working:

bad_back.jpg (615.84 KiB) Viewed 69 times

bad_front.jpg (505.71 KiB) Viewed 69 times

board that is working:

good_back.jpg (525.85 KiB) Viewed 69 times

[mikeysklar]

Let's make sure the software is the same on the 7 boards that have been problematic.

When you enter bootloader mode (double reset press) what do you see in the INFO_UF2.TXT on a good board versus not working?

The current bootloader is v3.14.0

https://github.com/adafruit/uf2-samdx1/ ... 3.14.0.uf2

Are you using CircuitPython? If so please make sure the same CircuitPython release and library bundle is being used.

Failing CAN initialization is a useful data point. We should probably rule out any configuration difference before getting deeper into the init fail.

[owenp]

I checked both the problematic and working boards, they all have v1.23.1-adafruit.1-336-gbcaa5b1-dirty SFHWRO as the bootloader.

I updated the problematic boards to 3.14.0 and this did not fix the issue.

I am using the Arduino IDE to upload code to these boards.

[mikeysklar]

Since these the working and non-working boards appear identical we should try a replacement on the fussy 7 units.

The PCB markings, bootloader and code has been the same so I don't see an issue on your side.

Please e-mail support@adafruit.com requesting a replacement for 7 units. Your invoice# and link to this forum thread will be necessary.

[adafruit2]

owenp - did you enable the boost converter
https://learn.adafruit.com/adafruit-fea ... ss/pinouts