Open mgiacomelli opened 3 years ago
Did you get anywhere with this? I have some ATSAMD21E17A boards on the way and am hoping I can get a bootloader on them.
I have a fork of this repo which adds support for some custom boards based on the ATSAMD21E17A, if you want an example of how to make this work.
Lately the SAMD21G series processors have become scarce (one supplier quoted me a 12 month lead time) due to the chip shortage. To address this I was hoping to get an Arduino environment up on some of the easier to find SAMD variants like the SAMD21E17A which is the same expect with half the RAM/flash. I added a new Trinket M0 based board with a new board_config.h, board.mk with the correct and edit samd21j18a.ld to have half of the RAM/flash. Finally I added a ATSAMD21E17A device to Atmel.SAMD21_DFP.pdsc, although I'm not sure if that was needed.
I can compile and flash the bootloader with ST-LINK, and it will appear to work and present the UF2 MSC volume. I can even copy an updated .uf2 image to that volume and then boot into the updated image. However, as soon as I unplug the device and then plug it back in, the board goes dead until I reflash it with the ST-LINK. Apparently something about a cold boot crashes it where a hot boot does not.
I read through #132 and #96 which describe similar problems on the smaller SAMD boards, but these eventually get to BOSSA, which I believe I am not even using yet since I'm just flashing with the ST-LINK. At this point I'm a little stuck. Is there some way I can trouble shoot what happens on power up?