Siemens SIMATIC S7 CP340 Programming Manual page 38

5 MODBUS RTU Protocol communication
corresponding Siemens data area is M0.0-M12.4. 101 to 200 match the MODBUS
Address area 00102 to 00201, and the corresponding Siemens data area is Q0.0
to Q12.3. The slave addresses 201 to 300 and 301 to 400 match the Modbus
address areas 00202 to 00301 and 00302 to 00401, and the corresponding
Siemens data area is Timer, Counter.
Fig. 62: Distribution of MODBUS Slave addresses
6. FC02 reads input data status, and the address matching is as stated above.
Fig. 63: Distribution of MODBUS Slave addresses
7. FC03,06,16 configuration output register data area corresponds to Siemens
data area DB block.
Fig. 64: Distribution of MODBUS Slave addresses
8. FC04 configuration input register data area also corresponds to Siemens data
area DB block.
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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