DVP-ES2-EX2-SS2-SA2-SX2-Operation Manual

3. Instruction Set
Value
H0005
Error Description
Communication data length error
9. Corresponding table between D1167~D1169 and the associated interrupt pointers. (Only
lower 8 bits are valid)
COM Port I1□0 interrupt Special D
COM1 I140 D1167
COM2 I150 D1168
COM3 I160 D1169
10. Take standard MODBUS format for example:
ASCII mode
Field Name
STX
Address Hi
Address Lo
Function Hi
Function Lo
DATA (n-1)
…….
DATA 0
LRC CHK Hi
LRC CHK Lo
END Hi
END Lo
Descriptions
Start word = ‘: ’ (3AH)
Communication address:
The 8-bit address consists of 2 ASCII codes
Function code:
The 8-bit function code consists of 2 ASCII codes
Data content:
n × 8-bit data content consists of 2n ASCll codes
LRC check sum:
8-bit check sum consists of 2 ASCll code
End word:
END Hi = CR (0DH), END Lo = LF(0AH)
The communication protocol is in Modbus ASCII mode, i.e. every byte is composed of 2 ASCII
characters. For example, 64Hex is ‘64’ in ASCII, composed by ‘6’ (36Hex) and ‘4’ (34Hex). Every
character ‘0’…’9’, ‘A’…’F’ corresponds to an ASCII code.
Character ‘0’ ‘1’ ‘2’ ‘3’ ‘4’ ‘5’ ‘6’ ‘7’
ASCII code 30H 31H 32H 33H 34H 35H 36H 37H
Character ‘8’ ‘9’ ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘F’
ASCII code 38H 39H 41H 42H 43H 44H 45H 46H
Start word (STX): ‘: ’ (3AH)
Address:
‘0’ ‘0’: Broadcasting to all drives (Broadcast)
‘0’ ‘1’: toward the drive at address 01
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