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Modbus

In WebHMI, such syntax of addressing ModBus (RTU/ASCII/TCP) registers is defined:

Register address Description Data type Read(FC1))/Write(FC)
Cx Coils. X — output number (valid range is 0..65535). Examples: C1, C3, C44 Bit Read(0x01)/Write(0x05)
DIx Discrete Inputs. X — input number (valid range 0 ..65535). Examples: DI1, DI3, DI44, DI45000 Bit Read(0x02)/—
HRx Holding Registers. X — register address (valid range 0..65535). Examples: HR1, HR3, HR44, HR65043 Bit, Byte, Word, Double Word Read(0x03)/Write(0x06)
MHRx Identical to HRx. The difference is that the writing in such registers occurs using the Modbus function No. 16 (Preset Multiple Register). Bit, Byte, Word, Double Word Read(0x03)/Write(0x16)
IRx Input Registers. X — register address (valid range 0..65535). Примеры: IR1, IR3, IR44, IR65043 Bit, Byte, Word, Double Word Read(0x04)/—
ATTENTION! By default, for double word reading, two queries each by one word will be used. To explicitly set 
double-word  reading with one query (multiple read), you must enable grouping in the connection properties.
1)
FC - function code used

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