Chapter 4 Parameters
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Step 6: Repeat step 2 to 5 for the next 8-bit byte of the command message. Continue doing
this until all bytes have been processed. The final contents of the CRC register are the CRC
value. When transmitting the CRC value in the message, the upper and lower bytes of the
CRC value must be swapped, i.e. the lower order byte will be transmitted first.
The following is an example of CRC generation using C language. The function takes two
arguments:
Unsigned char* data
a pointer to the message buffer
Unsigned char length
the quantity of bytes in the message buffer
The function returns the CRC value as a type of unsigned integer.
Unsigned int crc_chk(unsigned char* data, unsigned char length){
int j;
unsigned int reg_crc=0xFFFF;
while(length--){
reg_crc ^= *data++;
for(j=0;j<8;j++){
if(reg_crc & 0x01){ /* LSB(b0)=1 */
reg_crc=(reg_crc>>1) ^ 0xA001;
}else{
reg_crc=reg_crc >>1;
}
}
}
return reg_crc;
}
3.5 Address list
The contents of available addresses are shown as below:
Content Address
Function
AC drive
Parameters
GGnnH
GG means parameter group, nn means parameter number,
for example, the address of Pr 04.01 is 0401H. Refer to
chapter 5 for the function of each parameter. When reading
parameter by command code 03H, only one parameter can
be read at one time.
Command
Write only
2000H
Bit 0-1
00B: No function
01B: Stop
10B: Run
11B: Jog + Run
Bit 2-3
Reserved
Bit 4-5
00B: No function
01B: FWD
10B: REV
11B: Change direction
Bit 6-7
00B: Comm. forced 1st accel/decel
01B: Comm. forced 2nd accel/decel
