Question about uploading to Arduino IDE using SAMD21G17D chip

[powerdeng]

Hello, I made a board with the same configuration as the Adafruit Feather M0 (SAMD21) with SAMD21G17D chip. I replicated the Arduino Zero bootloader file by referring to the link here. (Creating a custom SAMD bootloader and Arduino board)

And I renamed the samd21g18a_flash.ld and samd21g18a_flash.ld files to 21g17a and resized the memory.

Also, after renaming bootloader_samd21X18.ld to samd21X17.ld, I modified the code as below and changed LD_SCRIPT=bootloader_samd21x18.ld to LD_SCRIPT=bootloader_samd21x17.ld in Makefile. This is how you built the bootloader.

To recognize the SAMD21G17D chip like the link above, we rebuilt bossac.exe and changed the maximum_size and extra_flags in boards.txt as shown below.

And in the process of compiling and uploading sketches in Arduino IDE 2.1.1, the following error occurs. Can you help me with this?

[markd833]

Ah, seen that one several times when rebuilding bossac.

If I remember, it's caused by the "-U true" bit of the command line.

I think the version of bossac you have rebuilt wants "-U=true".

I need to check the exact details but I think you may be using a slightly newer or older version of bossac.

EDIT: Another thought came to me. I think I based my addition to the boards.txt file on an Arduino Zero rather than an Adafruit feather. I think that changed the bossac command line slightly and the error disappeared.

I will check and report back.

[powerdeng]

Thank you for your reply.
I checked and found that I was using Adafruit bossac source code. So I'm currently trying to build another Arduino bossac source code. I tried to build it after seeing what you wrote earlier, but it didn't build, so I'm looking for a way.
I'll look for more.

[markd833]

You might find these useful. They are the notes I made on building a new BOSSAC and configuring a new bootloader for my SAMD21G17D. I'm pretty sure that I selected an Arduino Zero as my board when I wanted to download code to the SAMD.

Instructions to build a new BOSSAC v1.0.pdf (217.2 KB)
Building a SAMD21 Arduino Compatible Bootloader v1.0.pdf (203.4 KB)

[powerdeng]

Thank you for providing good data.

I proceeded according to the method you told me, but the same error occurred with the message below.

"Force reset using 1200bps on port COM15"

Is there a possibility that it's another problem?

[markd833]

I need to get my Curiosity board out and take a look at my setup. I'll report back exactly what I do to upload to the SAMD.

[markd833]

I've got a feeling that the BOSSAC that Adafruit have used might not be based on the latest version.

I've not poked around BOSSAC to see if you can run it from the command line to get it to report its version number.

It would be useful to know what version of BOSSAC they used.

You could try and copy the BOSSAC command line from the IDE and run it separately from a command prompt and see what happens if you change the "-U true" to "-U=true".