global:
- test USB 5 bit reset

UART mode:
- add hex display for receive mode
- add error check command: display when parity, noise, or frame errors are detected
- add parity check on receiving side
- add general communication parser
- add flow control
- allow transmitting 9 bits in communication mode
- show 9 bits in receive hex mode
- add baud rate detection
- release peripheral on quit

I2C mode:
- monitor (while logic analyser is not supported)

SPI:
- support multiple slave selects
