PC to CPU:
'STX' 'ADR' 'P' 'CHK' 'ETX'
'P'
ASCII-Code 0x50 OR 0x80 = 0xD0
Example:
ADR = 1
String =
0x02 0x81 0xD0 0xD1 0x03 (5 Bytes)
CPU to PC
'STX' 'ADR' 'P' XXX 'CHK' 'ETX' (read value)
'P'
ASCII-Code 0x50 OR 0x80 = 0xD0
XXX
actual program number (3 ASCII characters, 001-099) 000 = no program currently running
Example:
ADR = 1, program 1 runs (HEX 0x30 or HEX 0x80, HEX 0x30 or HEX 0x80, HEX 0x31 or HEX 0x80)
String =
0x02 0x81 0xD0 0xB0 0xB0 0xB1 0xE0 0x03 (8 Bytes)