hpmont HD3N Series, Руководство пользователя

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Appendix B Communication Protocol Shenzhen Hpmont Technology Co., Ltd.
- 150 - HD3N Series User Manual V1.1
6. CRC checking
Code of online calculating CRC is shown below:
unsigned int crc_check(unsigned char *data,unsigned char length)
{
int i;
unsigned crc_result = 0xffff;
while(length--)
{
crc_result^ = *data++;
for(i = 0;i<8;i++)
{
if(crc_result&0x01)
crc_result = (crc_result>>1)^0xa001;
else
crc_result = crc_result>>1;
}
}
return (crc_result = ((crc_result&0xff)<<8)|(crc_result>>8));
}
7. Application Case
Remarks: Please verify all the hardware equipments are connected well before controlling the
controller via communication. In addition, please preset the communication data format, baud rate
and communication address.
1. To read max. output frequency of address 2(to read command Frame F00.06), response Frame =
50.00Hz
Command
Frame
Address Code Register address Word no. of read Checksum
0x02 0x03 0x00 0x06 0x00 0x01 0x64 0x38
Response
Frame
Address Code Answer byte Register content Checksum
0x02 0x03 0x02 0x13 0x88 0xF1 0x12
2. To read the DC bus voltage of address 2 ( group d00), corresponding answer Frame = 537V)
Command
Frame
Address Code Register address Word no. of read Checksum
0x02 0x03 0x33 0x19 0x00 0x01 0x5A 0xBA
Response
Frame
Address Code Answer byte Register content Checksum
0x02 0x03 0x02 0x02 0x19 0x3C 0xEE