I'm working on reversing a USB flash drive controller chip. I know there's a microprocessor that runs some 8051 variant, and I have the ability to run arbitrary code on it. There's lots of different 8051-like manufacturers though, and I'd like to find out the specific processor model on this specific chip.
I don't think the reason is relevant, but it's because I'm interested in breaking a model-specific code protection mechanism, and I need to know the model for it.
My question is, is there some standard way to find out the model/manufacturer of the processor? Maybe a special function register that holds a vendor specific signature, or something akin to x86's CPUID. I could break the chip and look for the processor within but I'd really prefer not to do that.