Appendix II
74
A
p
p
en
d
ix
II
the most significant bit(MSB) is filled with 0. LSB will be picked up for detection, if LSB is 1,
the register will be XOR with the preset value separately, if LSB is 0, then no XOR takes place.
The whole process is repeated eight times. After the last bit (eighth) is completed, the next eight-
bit byte will be XOR with the register's current value separately again. The final value of the
register is the CRC value that all the bytes of the message have been applied.
When the CRC is appended to the message, the low byte is appended firstly, followed by the
high byte. CRC simple functions is as follows:
unsigned int crc_chk_value(unsigned char *data_value,unsigned char length)
{
unsigned int crc_value=0xFFFF;
int i;
while(length--)
{
crc_value^=*dat+;
for(i=0;i<8;i++)
{
if(crc_value&0x0001)
{
c r c _ v a l u e = ( c r c _ v a l u e > > 1 )^0xa001;
}
else
{
crc_value=crc_value>>1;
}
}
}
return(crc_value);
}
II -3
Definition of communication parameter address
The section is about communication contents, it’s used to control the operation, status and
related parameter settings of the inverter. Read and write function-code parameters (Some
functional code is not changed, only for the manufacturer use or monitoring): the rules of
labeling function code parameters address:
The group number and label number of function code is used to indicate the parameter
address:
High byte: F0 to Fb (F group), A0 to AF (E group), B0 to BF(B group),C0 to C7(Y
group),70 to 7F (d group) low byte: 00 to FF
For example: address F3.12 indicates F30C; Note: L0 group parameters: neither read nor
change; d group parameters: only read, not change.
Some parameters can not be changed during operation, but some parameters can not be
changed regardless of the inverter is in what state.When changing the function code parameters,
please pay attention to the scope, units, and relative instructions on the parameter.
Besides, due to EEPROM is frequently stored, it will redUce the life of EEPROM, therefore
under the communication mode some function code do not need to be stored and you just change
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