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- Create separate mutex for SPI vs User data handling
Problems:
A: Memory/Data conflicts became apparent after time without thread-safe
queues
B: Without implementing locking at the SPI level, even simple code
examples (rx_transfer.cpp) would hang if a write was done out of sync
with reads

Solutions:
A: Keep initial locking mechanism for users
B: Implement separate automatic mutex and locking mechanism for SPI

#172 #173