Attaching a Debugger

See the Hacktribe Debrick Guide for more details on getting a debugger attached.

CPU

For the CPU, a JLink EDU and JLinkGDBServer works well. We can also use a Raspberry Pi and OpenOCD.

If using JLink, connect the debugger to USB host, then power electribe using modified power switch. Then run:

JLinkGDBServer -device am1802 -speed 0

If using Raspberry Pi, OpenOCD will exit if the electribe is not powered, but the electribe will boot if OpenOCD is not attached, so we need some trickery. First power up electribe, then run OpenOCD, then power off electribe with OpenOCD still running. Then power up electribe again before restarting OpenOCD. It is a lot easier to use a JLink.

Once you have a gdb server attached to the CPU, change directory to freetribe/cpu and run:

arm-none-eabi-gdb

The commands in freetribe/cpu/.gdbinit should connect to the gdb server, load the symbols from cpu/build/cpu.elf and run the firmware. You may need to edit the port number in .gdbinit. OpenOCD uses 3333 by default, with JLinkGDBServer using 2331.

If all is well, you should hit a breakpoint at main.
Other useful breakpoints may be knl_init, knl_run, app_init and app_run.

DSP

For the DSP, I've only managed to get the official debugger from Analog Devices working.
The ADSP-ICE-1000 costs around £180 (thank you sponsors) and is very much a one-trick pony. I will try again to get the Raspberry Pi set up with the DSP, but I'm not sure if the Analog Devices OpenOCD fork is even supposed to support this.

The good news is, the DSP firmware is loaded by the CPU. So if you can deal without debugging you can still load and run your code.

If you have a debugger for the DSP, first run the binary on the CPU. By the time the CPU reaches app_run the DSP kernel will be running.

Change directory to freetribe/dsp and run:

sudo openocd-bfin -s /usr/share/openocd-bfin/scripts \
                  -f /usr/share/openocd-bfin/scripts/interface/ice1000.cfg \
                  -f /usr/share/openocd-bfin/scripts/target/bf527.cfg

Then in another shell in the same directory:

bfin-elf-gdb

The commands in freetribe/dsp/.gdbinit should connect to the gdb server, load the symbols from freetribe/dsp/build/bfin.elf and set a breakpoint at module_process, the audio processing callback.

I will try to add new sysex functions to Hacktribe, so we can load and execute code without needing a debugger.