Veichi SD710 Series, User Manual

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SD710 Series Servo Drive User Manal Chapter 11 Communication
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(5) 06H command code writes 1 word
Function: Write 1 word.
Example: Write 1000 (03E8H) to address 0A00H of servo drive with station number 01H.
Table 11-3 0x06 Command to Write a Word
Command message (master) Response message (slave)
Address 01H Address 01H
Command 06H Command 06H
Start data address
0AH
Start data address
0AH
00H 00H
Data content
03H
Data content
03H
E8H E8H
CRC check code
8AH
CRC check code
8AH
ACH ACH
(6) 10H command code writes 2N words
Function: Write N words (Word ), N ≥ 2.
For example, write 100 to the address 0100H of servo drive with slave address 0100H and 400 to the address 0101H of
servo drive with slave address 01H
Table 11-4 0x06 Command to write 2N words
Command message (master) Response message (slave)
Address 01H Address 01H
Command 10H Command 10H
Write data address
01H
Write data address
01H
00H 00H
Number of data
00H
Number of data
00H
02H 02H
byte number 04H
CRC check code
40H
Data content 1st word high byte 00H 34H
Data content 1st word low byte 64H - -
Data content 2nd word high byte 01H - -
Data content 2nd word low byte 90H - -
CRC check code
BEH
-
-
1CH -
(7) RTU mode check code calculation
RTU mode uses CRC (Cyclical Redundancy Check) to detect error values.
The calculation of the CRC detection value is illustrated in the following steps.
Step 1: Preset a 16-bit register with the content of FFFFH, called CRC register.
Step 2: Perform XOR operation of the first byte (Address) of the command message and the low byte of the 16-bit CRC
register, and the result is stored back into the CRC register.
Step 3: Check the lowest bit (LSB) of CRC register, if this bit is 0, then shift right one bit; if this bit is 1, then shift right one
bit of CRC register value and then perform the XOR operation with A001H.
Step 4: Go back to step three until step three has been performed eight times before going to step five.
Step 5: Repeat steps 2 to 4 for the next byte of the command message until all bytes have been completely processed.