I am a student and I am doing my first attempt with a Modbus device, the one that I have is the S6899 (from: http://www.shjelectronic.com/ZigbeeModules.htm)

I already try a lot of things but I can't read/write the device registers, my hardware setup is a 12VDC power supply for the S6899, then an Ethernet cable to a Linksys WRT 120N. My PC has Windows 10, and I am trying to read/write the device using Modscan32.

As I say I am very new so please forgive if I say some nonsense. I suppose that I can see the S6899 IP on the router DHCP Clients List, but when I look into it I can only see my PC's IP.

I appreciate any help, and sorry for my English as you can see I am not very skilled at it.

 

Modscan32 is a generic Modbus master.

The S6899 is a serial server that converts from one hardware bus to another hardware bus. It is not a Modbus slave, it has no Modbus registers.

The S6899 might be used to convert a Modbus/TCP ethernet poll message from Modscan32 (running on your PC) to a Modbus RTU formatted message on RS-485 or RS-232 bus in order to communicate to a Modbus slave which has registers at a slave node address.

Your network is not a Modbus network, it does not have a Modbus slave with registers.

There is nothing for Modscan to talk to.

It's like you if speak into a telephone. The telephone converts your audio speech to an electronic signal that gets converted back into audio sound at the other end.

Modscan is the speaker, the converter is the telephone, but there's nothing on the other end to hold a conversation with.