Siemens SIMATIC S7 CP340 Programming Manual page 61

5 MODBUS RTU Protocol communication
3. When testing different function codes, just modify the data request telegram
sent by the master.
Fig. 110: Create send data frame
Fig. 111: Invoke SFB13 in OB1
5.4 MODBUS Slave protocol communication of CP441-2
5.4.1 Hardware catalog
RACK-400
PS407
CPU414-3
CP441-2
Dongle
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0,
6ES7400-1JA01-0AA0
6ES7407-0KA02-0AA0
6ES7414-3XJ04-0AB0
6ES7441-2AA03-0AE0
6ES7870-1AB01-0YA0
02/2014
61