5 MODBUS RTU Protocol communication
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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Fig. 78: Floating point number data processing
At this moment, the floating point number 40001 displayed in Modscan32
corresponds to the floating point number value of MD200, but MODBUS address
corresponds to DB1.DBD0.
Fig. 79: Floating point number data exchange
If CP341 module with RS422/RS485 interface is used, RS422/485 converter shall
be used when using computer serial port debugging program.
5.2
MODBUS Master protocol communication of CP341
5.2.1
Hardware catalog
PS 307
6ES7 307-1EA00-0AA0
CPU 315-2DP
6ES7 315-2AG10-0AB0
MMC
6ES7 953-8LG11-0AA0
CP341
6ES7 341-1AH01-0AE0
Dongle
6ES7 870-1AA01-0YA0
Insert Dongle into CP341, and the Dongle and CP341 before and after Dongle is
inserted are shown in the Fig. below: