ATSAM3U4 bootloader problem

RE: ATSAM3U4 bootloader problem

MC — Mon, 21 Dec 2015 13:26:09 GMT

I've solved my problem. If someone else encounters the same problem, here is what I figured out by myself. You have to get yourself CMSIS-DAP bootloader and interface firmware from mbed's github: github.com/.../CMSIS-DAP Then, you open the bootloader project in Keil, build it and flashit with an external programmer. The issue was, that for flashing into boot sector of ATSAM IC, you have to change the range in flashing algorithm from 0x80000 to 0x00. By doing this, you enable flashing to that part of the flash. For interface FW I followed a similar procedure, only difference was, I had to flash FW to address 0x5000. Once all of this was done, I started up the board in bootoader upgrade mode and flashed J-link interface on it. It works as new, so I consider it a successfull repair.

RE: ATSAM3U4 bootloader problem

RK — Sat, 05 Dec 2015 01:36:49 GMT

Perhaps you should try the CMSIS-DAP/MBED forums, if there's any expertise in building and flashing CMSIS-DAP to a chip, it'll be there. They use Keil to build it and should even have documentation about how it's built and flashed. If you can get MBED onto the chip you can probably then reload the Segger image.

Or buy a new DK

RE: ATSAM3U4 bootloader problem

MC — Fri, 04 Dec 2015 13:44:26 GMT

Hi, I have an Ulink 2 programmer with me, so there should be no problem regarding this. I can read device signature from Keil, so I know it works.

The problem is more in terms of actual flashing procedure, i.e. to which address should I flash the CMSIS-DAP firmware and how can I erase the stock SAM-BA bootloader which is already on the ATSAM chip? Do I even need to erase it, or should I flash CMSIS-DAP "behind" the stock bootloader?

-Matic

RE: ATSAM3U4 bootloader problem

Anders Strand — Fri, 04 Dec 2015 13:32:13 GMT

Hi.

The stock bootloader is made by Segger, and is not something i have access to unfortunately.

You might make it work by flashing the mBed CMSIS-DAP firmware to the ATSAM chip. In order to flash anything to the ATSAM chip, you need a programmer/debugger compatible with it. I am not sure what interface it supports, but i am guessing JTAG or SWD. (You can not program it with the usb connector on the board).

You could also try to connect directly to the nRF51 with an external JLINK adapter from Segger, or a cheaper CMSIS-DAP debugger.

-Anders