3 character data – Varec 4000 User Manual
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4000
Modbus Implementation
9.5.2
Integer Data
•
Hexadecimal representation
•
4124Decimal equivalent: 16,676
The data returned for data address 56 is 16,676 (4124 Hex). This value must be scaled using the following formula to
give it meaning.
If a variable goes out-of-bounds (outside the minimum or maximum scale points), a value equal to the maximum
Modbus integer + 1 is returned. Writing to dynamically calculated parameters has no effect on those parameters.
9.5.3
Character Data
Character data, such as software version, are returned in registers in ASCII data format. Each Modbus register
represents two ASCII characters.
The following communication example shows the character data "ATT-" read from the ATT.
•
Hexadecimal representation 41 54 54 2D
•
ASCII representation: ATT-
Host Request
Address
Function
Code
Start Reg
H
Start Reg
L
# of Reg
H
# of Reg
L
Error
Check
01
03
00
1E
00
02
XX
ATT Response
Address
Function
code
Byte
Count
Data
MSB
Data
LSB
Data
MSB
Data
LSB
Error
Check
01
03
04
41
54
54
2D
XX