Help with interpreting this manual using hexadecimal message
Here is a sample message from Master to Slave to turn the laser ON:
0xAA 0x55 0xC1 0x01 0x01 0x01 0x00
|_______|  |    |    |  |________| 
 header    |    |   data   parity
        Command |
              Data length

Here the command is 0xC1, which must be accompanied with data of length 1, telling ON or OFF. The parity is the data bytes added - which is simply 0x0001 in little endian