Manual

46 VEGACOM 557 Modbus
Data transmission with Modbus ASCII
Start
Slave
address
Functions
code
Address of the
1. register bit
Number of
register bits
Error
Check
End
No. of
bytes
Value
range
Meaning
Structure of enquiry acc. to switching conditions from Modbus master to VEGACOM
557
ASCII enquiry telegram acc. to switching conditions (function code 01)
12 2 4 4 2 2
:
1 .. 247
01
0 ... 65.509 8 ... 2.040
LRC CR LF
Start
Slave
address
Function
code
No. of
data bytes
Error
Check
End
No. of
bytes
Value
range
Meaning
Structure of the answer VEGACOM 557 to Modbus master
SCII answer telegram (function code 01)
1
22
2
2 bytes each for 8
register bits
22
:
1 .. 247
01
1 ...
255
LRC
CR LF
Data (switching conditions)
Switching condi-
tions to
AR card #4
Switching condi-
tions to
AR card #3
:010100200020XXCRLF
:
0
1
0
1
0
0
0
F
0
4
0
0
0
FX
X
CR
LF