I have taken apart an RB, but I don't know if I still have the carcass.
The main boards are almost identical to the older UGOBE boards. You probably won't learn much by looking at them.
The new head board is totally different, but the main chips (two new ARM? CPUs) are just epoxy blobs. No part numbers on them.
For determining protocols between the chips, you are probably better off attaching a scope to a partially disassembled (but still working) Pleo/PleoRB.
For firmware, I have the ARM firmware for the body CPU (for both models) and the head CPU for the older models. However you need to disassemble the ARM code and use the processor specs to figure out what is actually going on.
If you were trying to hack the CPU communication, that is where I would start (either a hardware or software approach)
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It sounds like you are doing some form of report on the guts of the Pleo/PleoRB. Do you have a Pleo/PleoRB at your disposal ?
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>@PLEOPET -> Could you tell me How runs the protocol when you use a program into SD? Is it loaded to DataFlash 8M or something similar data memory?
For regular use program, they run an interpreted Pawn program stored the DataFlash memory.
Read/re-read the documentation that comes with both the UGOBE PDK and the newer PleoRB PrbDK. They explain the way it works in some detail, along with how you can write your own Pawn programs.
However this is limited to Pawn programs running at a relatively high level. You have primitives that move the leg servos for you. The details of how it is done by the robot's firmware are hidden from you.