I have a question about reverse engineering a Roland gr-55 guitar synthesizer. I'm 90% sure the device uses a Renesas sh7722 processor as the main CPU, or at least one of the CPU's in the SH family. I first tried to disassemble the firmware binary using IDA, I then realized that IDA doesn't support the exact processor I have. On Renesas' website all the development tools are available along with a debugging emulator (E10A-USB emulator). My question is, am I able to use this emulator with my device? According to the user manual for the E10Aa-USB emulator (pg.31) the devices uses either a 14 pin or 36 pin connector which connects from the emulator to the user system or (gr-55 PCB board). According to the schematics for the Roland gr-55 (pg.34) top left corner of the page you can see a 24 pin connector labeled 24FLT-SM2-TB unpop for debug. So it seems the debugging port for the gr-55 is a 24 pin connector. So did the manufacture use their own custom emulator designed for just this board? Can there be multiple emulators for a processor, or is it that the main CPU is not a Renesas sh7722 and the E10A-USB is the wrong emulator. If the manufacture of the board did use their own custom emulator, is there any way to find and acquire the correct one? I'll post the schematics for the Roland GR-55 and the emulator user manual below.
Also on the board the 24 pin connector is not present, but it seems the outline for the connector is there for me to solder it to the board. So it seems if I find the right emulator I would have to solder on the 24 pin connector first.
My main goal is to be able acquire all the right development software and equipment for this unit, learn the assembly language for this processor, and disable the checksum so i'm able to change the names of strings and maybe some other functions making the UI for this system 1000x more usable.
If someone can clear this up for me I would greatly appreciate it.