CET PMC-1304-3, User Manual

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Ceiec Electric Technology
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Chapter 5 Modbus Register Map
This chapter provides a complete description of the Modbus register map (Protocol Version 1.1 and
above) for the PMC-1304-3-R communication processor to facilitate the development of 3
rd
party
communication driver for accessing information on the RTU Model.
The PMC-1304-3-R supports the following Modbus function:
1) Read Holding Registers (Function Code 0x03)
2) Force Single Coil (Function Code 0x05)
3) Preset Multiple Registers (Function Code 0x10)
For a complete Modbus Protocol Specification, please visit http:// www.modbus.org .
5.1 Analog Input Register
Register Property Description Format
40000 RO AI1 Float
40002 RO AI2 Float
40004 RO AI3 Float
… RO … Float
44094 RO AI2048 Float
Table 5-1 AI Measurements
Notes:
1) When the AI x ’s reading is 0x7fffffff, the register value is invalid. For example, when the AI’s
corresponding IDE cannot be connected normally; the register’s reading would be 0x7fffffff.
5.2 Digital Input Register
Register Property Description Format
45000 RO DI01~DI16 UINT16
45001 RO DI17~DI32 UINT16
45002 RO DI33~DI48 UINT16
… RO … UINT16
45127 RO DI2033~DI2048 UINT16
45128 RO SOE Total
1
UINT32
Table 5-2 DI Measurements
Notes:
1) The range of the registers is between 0 and 0xFFFFFFFF, the register will roll over to 1 if its
current value is 0xFFFFFFFF, as the resetting register will be recorded as a SOE event. The
master will read the register’s value and compare with last reading.

If the latest value is same as the last value, there is no newly SOE event.

If the latest value is different from the last value, there are newly SOE events. For example,
the last reading and the latest reading are 10 and 15, respectively, then there are 5 newly
SOE events.
2) Each of connected devices will be defined as a virtual DI to show communication status, where 1
means Connected , while 0 means Disconnected.