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Appendix
Specification of SN200G high-performance vector convertor
- 170 -
RTU frame format
Frame header START
Time of 3.5 characters
Slave ADR
Address: 1~247
CMD code
03: read slave parameters; 06: write slave parameters
DATA (N-1)
Data content: address of function code parameters, number
of function code parameters, value of function code
parameters, etc
DATA (N-2)
……
DATA0
CRC CHK high-order Detection value: CRC value
CRC CHK low-order
END
Time of 3.5 characters
CMD
and
DATA
CMD code: 03H, read N word (12 words at most). For example: start address F002 of frequency
convertor with slave address being 01 reads 2 values successively
CMD message of host
ADR
01H
CMD
03H
Start address high-order
F0H
Start address low-order
02H
Register No. high-order
00H
Register No. low-order
02H
CRC CHK high-order
CRC CHK value to be calculated
CRC CHK low-order
Response message of slave
PD-05
is set as
0
:
ADR
01H
CMD
03H
Byte No. high-order
00H
Byte No. low-order
04H
Data F002H high-order
00H
Data F002H low-order
00H
Data F003H high-order
00H
Data F003H low-order
01H
CRC CHK low-order
CRC CHK value to be calculated
CRC CHK high-order