RKC INSTRUMENT PG500, Communication Instruction Manual

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4. MODBUS COMMUNICATION PROTOCOL
IMR02F04-E1
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4.8 How to Use Modbus Data Mapping
In this communication, it is possible to continuously read/write data by freely specifying 16 sets of data.
Register address to specify mapping data: 1000H to 100FH
Register address to actually read/write data: 1500H to 150FH
Register address of data which can be mapped: Refer to 5.2 Communication Data List (P. 44) .
For the data mapping address list, refer to the 4.9 Modbus Data Mapping Address (P. 40)
.
Example 1: When mapping Measured value (PV), Alarm 1 state monitor, Alarm 2 state monitor and
Alarm output state monitor to the register addresses from 1500H to 1503H
For data mapping
Mapping data
Name
Register address
Name
Register address
HEX DEC HEX DEC
Register address setting 1
Read/write address
: 1500H
1000 4096 Measured value (PV) 00E0 224
Register address setting 2
Read/write address
: 1501H
1001 4097 Alarm 1 state monitor 00E2 226
Register address setting 3
Read/write address
: 1502H
1002 4098 Alarm 2 state monitor 00E3 227
Register address setting 4
Read/write address
: 1503H
1003 4099 Alarm output state monitor 00EC 236
1. The register address, “00E0H” of the Measured value (PV) to be mapped is written to register address
setting 1 (1000H).
2. The register address, “00E2H” of the Alarm 1 state monitor to be mapped is written to register
address setting 2 (1001H).
3. The register address, “00E3H” of the Alarm 2 state monitor to be mapped is written to register
address setting 3 (1002H).
4. The register address, “00ECH” of the Alarm output state monitor to be mapped is written to register
address setting 4 (1003H).
5. The assignment of the register addresses from 1500H to 1503H from/to which data is actually
read/written becomes as follows.
Register address Name
HEX DEC
1500 5376 Measured value (PV)
1501 5377 Alarm 1 state monitor
1502 5378 Alarm 2 state monitor
1503 5379 Alarm output state monitor
Write to register address (1000H to 1003H)
High-speed communication is
performed by reading or writing
data in the consecutive register
addresses from 1500H to 1503H.