FR150A Series Multifunctional Compact
Inverter
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Command code 0x06: Write single function code or control parameter of inverter.
ADU Item
Byte No.
Range
Master requests:
Address of slave
1
0
～
127
Command Code
1
0x06
Register start address
2
0x0000
～
0xFFFF
The number of register
2
0x0000
～
0xFFFF
CRC parity
2
Slave responds :
Address of slave
1
The local address
Command Code
1
0x06
Register start address
2
0x0000
～
0xFFFF
The number of register
2
0x0000
～
0xFFFF
CRC parity
2
Command code 0x08: Circuit Diagnosis and Setting
ADU Item
Byte No.
Range
Master requests:
Address of slave
1
0
～
127
Command Code
1
0x08
Register start address
2
0x0000
～
0xFFFF
The number of register
2
CRC parity
2
Slave responds :
Address of slave
1
The local address
Command Code
1
0x08
Register start address
2
0x0000
～
0xFFFF
The number of register
2
CRC parity
2
Remarks:
Command code 0x08 is only for circuit check.
6
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CRC Parity
Sending equipment calculates CRC parity value first, and then attaches it to the sending
message. Upon receipt of the message, receiving equipment will calculate CRC parity value again,
and compare the operation result with received CRC parity value. If the two values are different, it
indicates that there is error during transmission.
Calculation process of CRC parity:
1. Define a CRC parity register, and initialize it as FFFFH.
2. Conduct XOR calculation between the first byte of sending message and the value of CRC parity
register, and then upload the result to CRC parity register. Start from address code, the start bit and
stop bit will not be calculated.
3. Collect and check LSB (the least significant bit of CRC parity register).
4. If LSB is 1, shift each bit of CRC parity register rightwards by 1 bit, the highest bit filled with 0.
Conduct XOR calculation between the value of CRC register and A001H, and then upload the result to
CRC parity register.
5. If LSB is 0, shift each bit of CRC parity register rightwards by 1 bit, the highest bit filled with 0.
6. Repeat steps 3, 4 and 5 until completing 8 rounds of shifting.
7. Repeat steps 2, 3, 4, 5 and 6, and process the next byte of sending message. Repeat above process
continuously until each byte of sending message is processed.
8. CRC parity date will be saved in CRC parity register after calculation.
9. LUT (Look-up table) method is to obtain CRC parity in the system with limited time resources.
Simple CRC functions as shown in following (C language Programming):
