Modbus TCP

[Seijboldt]

Hi,
I'm trying to read and write some values to a modbus device via script.
The device comes with some documentation, example:
3x0001 alarm status 1-30
1x0005 fault status 1/0
4x0045 outside temperature -50-50c

I've searched these forums and figured out how to read from the modbus TCP, however the function readregisters() doesn't really support running these types of addresses.

Is there any documentation if partial about modbus implementation?
Readregisters(address, modbus function) would make sense but it doesn't really seem to work that way.
I assume writing is writeregisters()?

(On a spacelynk btw)

Thanks,