Modbus TCP I/O module - can't read in Winlog

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Joined: Wed Jun 24, 2015 11:39 am

Modbus TCP I/O module - can't read in Winlog

Post by bctBCT76 »

Dear All,
i have an issue with a TCP/IP I/O module. I can see input and force each output through the browser control/test page of the module but I could not sett gates in Winlog to read or write to this module. I don't know how to do it.

I paste a part of the manual for this module:
Note: The ON/OFF state of discrete inputs and outputs is represented by a
1 or 0 value assigned to an individual bit in a 16-bit data word (port).
This is sixteen 0x or 1x references per data word. With respect to
mapping, the lsb of the word maps to the lowest numbered channel of
a port and channel numbers increase sequentially as you move
towards the msb.

All I/O values are accessed via the 16-bit Input Registers or 16-bit Holding
Registers given in the Register Map. Input registers contain information that
is read-only.

01 (01H) Read Coil (Output) Status 0xxxx
02 (02H) Read Input Status 1xxxx
03 (03H) Read Holding Registers 4xxxx
04 (04H) Read Input Registers 3xxxx
05 (05H) Force Single Coil (Output) 0xxxx
06 (06H) Preset Single Register 4xxxx
15 (0FH) Force Multiple Coils (Outputs) 0xxxx
16 (10H) Preset Multiple Registers 4xxxx
17 (11H) Report Slave ID (See Below) Hidden

0xxxx Coil Registers are mapped to 42xxx Holding Registers
1xxxx Input Status Registers are mapped to 41xxx Holding Registers
3xxxx Input Registers are mapped to 43xxx Holding Registers

For 3xxxx Input Registers, the format of the registers is identical and you
only need to offset your address by 43000. For example: if you want to read
Input Register 1 through the Holding Registers, you would use the “Read
Holding Registers” function with an address of 43001.

For the 1xxxx Input Status Registers, the return data is reformatted to match
the Holding Register format. For example: if you request the Input Status for
16 digital inputs, instead of getting 2 bytes returned with the 16 bits
representing the 16 digital inputs, you will get 16 separate words, each set to
either 0000H (OFF), or FFFFH (ON).

For the 0xxxx Coil Registers, reads are handled in the same way as the
1xxxx Input Status Registers. You can also write to the coil registers by
using the “Preset Single Register” function with an address offset of 42000.
Setting the data to 0000H will turn the coil OFF, while setting the data to
FF00H will turn the coil ON.
modbusTCP.png (242.57 KiB) Viewed 929 times
Can any one help me understanding how to setup gate values and addresses for this device or if a similar mapping is used in devices library available in Winlog?
Thanks everybody

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Re: Modbus TCP I/O module - can't read in Winlog

Post by admin »

Hi, please post your test application, we can check it.
What is the model of your device?


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