PIC is WAY too slow for doing the cryprographic functions and has not enough mem.
ARM is still way too slow for getting good hashrates
It's not doing the hashes, it's getting the work from the mining
pool to some FPGAs/ASIC that wil do the hashing. And when
a golden nonce is found the ARM will send it to mining pool.
So the processor is only doing the I/O to and from the mining
pool.
Can that be done?
intron
its possible, not actually much work to program if you just want it to act as a "thinker" for the ASICs brute force, I don't believe such a setup exists however it should not be insurmountable, if I have some time in the next few days I will play around with some UART code for TI stellaris launchpad.