hth313 / calypsi-remote-debug

Calypsi remote debug agent

This is a remote debug monitor or agent, implementing part of the gdbserver protocol intended to be used with the Calypsi C compiler.

Submodules

This project uses Git submodules. When you clone the project use the --recursive-submodules command line option. If you forget or have already cloned the project you can pull in submodules using the git submodule init and git submodule update commands.

Supported boards

The C256 Foenix U/U+ with a WDC65816 is supported using its serial port at 115220.

The A2560 Foenix U/U+ with a 68000 is supported using its serial port at 115220.

The HB68K08 single board computer with a 68008 is supported and its serial port works at 57600.

New targets

6502 support for the Commodore 64 using its VICE emulator has been tried, but so far I have not managed to make the serial port work. If you are interested, please give it a try getting it to work with the Swiftlink serial port, either on VICE or a real Commodore 64.

Porting to other boards should be fairly straightforward by replacing the low level communication functions.

The Foenix FMX has been added but is currently untested as I do not have access to any such machine.

The A2560K uses different addresses and a serial port with different speed factors.

Configure the port

On Linux you can use dmesg to figure out the serial port used on your host computer:

   $ sudo dmesg | grep USB
   ...
   [109191.143623] ftdi_sio 1-1:1.0: FTDI USB Serial Device converter detected
   [109191.151619] usb 1-1: FTDI USB Serial Device converter now attached to ttyUSB1

Here you can see that a FTDI serial device is attached to /dev/ttyUSB1.

You can configure the serial port on the host using:

$ stty 115200 -F /dev/ttyUSB1

An alternative is to use the screen utility program, which opens a terminal session. This also sets up the serial port and you can also test that the monitor responds to input.

$ screen /dev/ttyUSB1 115200

If you press a key the remote debug agent should respond with $S13#b7.

Protocol snooping

When working with the debugger agent it can be useful to be able to see the communications going on. You can use the interceptty program for this.

Once installed you can start it using:

$ interceptty /devttyUSB1

This will allocate a pseudo tty and the number is dependent on your system. One example of how to start debugger is to use:

$ db65816 --target-remote /dev/pts/8 application.elf

In this case you can inspect your /dev/pts directory to see what devices you have before and after starting interceptty.