Modbus Tables - Air-To-Water Systems; Holding Registers - Procon A1M Installation Manual

12. Modbus tables – Air-To-Water systems
Some BMS controllers can only read Modbus Holding Registers, so the MelcoBEMS MINI (A1M) also exposes all Discrete, Coil and Input Registers as Holding Registers.
The Discrete Input registers and Input registers are not writable so their equivalent Holding Register is read only and marked [READ ONLY].
Some BMS controllers may not be able to read signed register values (i.e. values which can be negative in value), so the A1M also exposes an unsigned version of those
registers (these registers will not return a negative value).
12.1.

Holding registers

Holding Registers are read using function code 03 and written to using either function code 06 or 16. Function code 06 is used when writing to a single holding register,
function code 16 is used for writing to multiple holding registers in the same command.
Holding Register (Analogue Output)
Register Name Addr
Modbus Slave ID 4
Modbus RS-485 Baud Rate 5
RS-485 Parity Type 6
Modicon
Details
Address
40005 Values 1 – 247 valid
0 = 9600
1 = 1200
2 = 2400
3 = 4800
4 = 9600
5 = 14400
40006
6 = 19200
7 = 28800
8 = 38400
9 = 56000
10 = 57600
11 = 115200
0 = None
40007 1 = Even
2 = Odd
Applicable Unit Type
31