The User Manual of JAC200 Series General Frequency Converter
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process shall repeat for 8 times. After the last digit (the 8 digit) is completed, the next 8-bit bytes shall be
different with the current value in the register. The final value in the register is the CRC value after all the
bytes are performed.
When adding the CRC into the message, and the low bytes should be first, and then the high bytes followed.
The simple function for CRC 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++
）
{
whether
（
crc_value&0x0001
）
{
crc_value=
（
crc_value>>1
）
^0xa001;
}
else
{
crc_value=crc_value>>1;
}
}
}
return
（
crc_value
）
;
}
The address of communication parameter is defined as the reading and writing function code parameter
(some function codes cannot be modified, since they are used only by the manufacturer or for monitoring
purpose):
C.3 Address marking rules for function code parameter
Make function code group number and mark number as the parameter address marking rules:
High byte: F0~FF(Group F), A0~AF(Group A), 70~7F(Group U)
Low byte: 00~FF
For example: whether the function code is F3-12, then the accessing address for function code is shown as
0xF30C;
Note:
Group FF: neither readable nor changeable to the parameters;
Group U: readable only but not changeable to the parameters.
Some parameters cannot be changed when the frequency converter is under the running state; some
