TX & RX: Fix block state to detect SOH, CAN, EOT characters from transmitter #1
Description
Currently BLOCK blindly assumes a complete block with SOH + CHK + DATA + CRC16.
This needs to be amended to check for SOH, CAN, and EOT control characters from rx and TX to handle:
- End of transmission (currently hangs)
- Cancellation of transmission
- Short blocks
- Long blocks