7300CV MODBUS COMMUNICATION PROTOCOL
File No. :PC-CV-08
Version : 1.A
Page :
3/34
The data length is varied with the command (Function).
SLAVE Address
Function Code
DATA
CRC CHECK
Signal Interval
** The interval should be maintained at 10ms between command signal and request
1.3 SLAVE Address
00H : Broadcast to all the drivers
01H : to the No. 01 Driver
0FH : to the No.15 Driver
10H : to the No.16 Driver
and so on...., Max to No. 254(FEH)
1.4 Function Code
03H : Read the register contents
06H : Write a WORD to register
08H : Loop test
10H : Write several data to register (complex number register write)
2.CMS (Checksum and time-out definition)
2.1 LRC
ex. ADDRESS 01H
FUNCTION 03H
COMMAND 01H
00H
DATA LENGTH 0AH
-----------------------
0FH------------ true complement
Checksum = F1H
CS(H) = 46H (ASCII)
CS(L) = 31H (ASCII)
2.2 CRC CHECK
:
CRC check code is from Slave Address to end of the data. The calculation method is illustrated as follow:
(1) Load a 16-bit register with FFFF hex (all's 1). Call this the CRC register.
