Powtran PI9100 Series Manual page 232

When F9.05
is set to 1:
ADR
CMD
Byte number
Data F002H high-order
Data F002H low-order
Data F003H high-order
Data F003H low-order
CRC CHK low-order
CRC CHK high-order
Command Code: 06H, write a word. For example:Write 5000(1388H)into the address F00AH
of the inverter with slave address 02H.
Master command information
ADR
CMD
Data address high-order
Data address low-order
Data content high-order
Data content low-order
CRC CHK low-order
CRC CHK high-order
Slave responding information
ADR
CMD
Data address high-order
Data address low-order
Data content high-order
Data content low-order
CRC CHK low-order
CRC CHK high-order
I-2 Check mode:
Check mode - CRC mode: CRC (Cyclical Redundancy Check) adopts RTU
frame format, the message includes an error-checking field that is based on CRC
method. The CRC field checks the whole content of message. The CRC field has
two bytes containing a 16-bit binary value. The CRC value calculated by the
transmitting device will be added into to the message. The receiving device
recalculates the value of the received CRC, and compares the calculated value to the
Actual value of the received CRC field, if the two values are not equal, then there is
an error in the transmission.
The CRC firstly stores 0xFFFF and then calls for a process to deal with the
successive eight-bit bytes in message and the value of the current register. Only the
01H
03H
04H
00H
00H
00H
01H
CRC CHK values are to be calculated
02H
06H
F0H
13H
13H
88H
CRC CHK values are to be calculated
02H
06H
F0H
13H
13H
88H
CRC CHK values are to be calculated
227
Appendix I