LSIS XBL-C41A

Chapter 10 Example Program
10-12
10.3
Modbus Communication
Example
We assume that system configuration of Modbus communication (Modbus RTU mode) example is as
[Figure 10.3.1] and communication setting is as following table.
[Figure 10.3.1] XGT Modbus communication system configuration example
• Mount XBL-C41A on no. 1 slot of client PLC
• Client setting
Main unit
XBM-DN32S
Communication
module
XBL-C41A(no.1 Slot)
Communication type
RS-485
Communication speed
38,400
Data bit
8
Stop bit
1
Parity bit
None
Operation cycle
200ms
Operation
status
Write
▶
Write 1 word of M100 of client to M1 of server
▶Write 4 words from D0 of client to M2~M5 of server
▶Write 15
th
bit of M2 to 2
nd
bit of M20 of server
▶
Write 0~15
th
bit of M2 to 0~15
th
bit of M21 of server
Read
▶
Read 1 word of M2 of server and save it at M160 of client
▶Read 4 words from P0 of server and save it at M150~M153
▶Read 1
st
bit of P2 of server and save it at 1
st
bit of M170.
▶
Read 0
th
~ 15
th
bit of M10 of server and save it at 0
th
~ 15
th
of M180 of client.
[Table 10.3.1] client setting
• Server setting
Main unit
XBC-DN32H
Communication type
Built-in RS-485
Communication speed
38,400
Data bit
8
Stop bit
1
Parity bit
None
Station no.
1
Start
address
Bit read area
Address
P0
Bit write area
Address
M0
Word write
area Address
P0
Word write
area Address
M0
[Table 10.3.2] server setting
Client
RS
-485, 38400, 8, 1, None, Modbus RTU
Server