SAJ VM1000 User Manual

VM1000 Series
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‐117‐
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When CRC is added to the message, the low byte will be added first and followed by
the high byte.The simple function of 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 ^= *data_value++;
for(i=0;i<8;i++)
{
if(crc_value&0x0001)
{
crc_value = (crc_ value>>1) ^ 0xa001;
}
else
{
crc_value = crc_ value >> 1;
}
}
}
return(crc_value);
}
Address definition of communication parameters: this part is the content of the
communication, which is used to control the VFD operation, VFD status and related
parameters setting (some function code can not be changed, only for factory use).
The rule of function code’s parameters address: high byte (F0 ~ FF), the low byte
(00 ~ FF); Like F3.12, the address is expressed as F30C.
Note: FF Group: Neither it can be readable parameters, nor modified parameters;
Therefore, some parameters can not be modified when VFD is at running status; No
matter in what status, some parameters can not be changed; When changing the
function code parameters, it still need to pay attention to the parameter range, unit
and related instructions.

SAJ VM1000 Specifications

General

Brand	SAJ
Model	VM1000
Category	Controller
Language	English