HV580L Series Frequency Inverter
193
ADR
02H
CMD
06H
Data address high order
P0H
Data address low order
0AH
Data content high order
13H
Data content low order
88H
CRC CHK low order
CRC CHK values to be calculated
CRC CHK high order
RTU salve response
ADR
01H
CMD
06H
Data address high order
P0H
Data address low order
0AH
Data content high order
13H
Data content low order
88H
CRC CHK low order
CRC CHK values to be calculated
CRC CHK high order
Cyclical Redundancy Check
:
Cyclical Redundancy Check
—CRC mode: CRC(Cyclical Redundancy Check) is in RTU frame format,
message contains an error-checking field that is based on a CRC method. The CRC field checks the contents
of the entire message. The CRC field is two bytes, containing a 16-bit binary value. The CRC value is
calculated by the transmitting device, which appends the CRC to the message. The receiving device
recalculates a CRC during receipt of the message, and compares the calculated value to the actual value it
received in the CRC field. If the two values are not equal, then results an error. The CRC is started by 0xFFFF.
Then a process begins of applying successive 8-bit bytes of the message to the current contents of the
register. Only the eight bits of data in each character are used for generating the CRC. Start and stop bits, and
the parity bit, do not apply to the CRC.
During generation of the CRC, each eight-bit character is exclusive XOR with the register contents. Then the
result is shifted in the direction of the least significant bit (LSB), with a ZERO filled into the most significant bit
(MSB) position. The LSB extracted and examined. If the LSB is 1, the register then exclusive XOR with a