Read Data
PC  "R"
EMU reset slave
PC  higher address byte
PC  lower address byte
PC  number of bytes (1-255)
EMU x bytes
EMU checksum byte

Write Data
PC  "W"
EMU reset slave
PC  higher address byte
PC  lower address byte
PC  number of bytes (1-255)
PC  x bytes
EMU checksum byte

Write to Program Memory
PC  "P"
EMU reset slave
PC  higher address byte
PC  lower address byte
PC  number of bytes (1-255)
PC  x bytes
EMU checksum byte

Get Version of EMU-µC
PC  "V"
EMU program version byte (0-255)

Start Slave
PC  "S"
EMU reset slave
EMU start slave