You can find a lot of relevant information on TRB141 in the following page: https://wiki.teltonika-networks.com/view/TRB141_Input/Output
For more specifics, regarding input/output control, below are a couple of suggestions:
For digital inputs/outputs and analog input status/values, there is a dedicated SMS command:
To control inputs, you can use uci command interface and try following commands:
- <routers_pass> uci set ioman.dio0.value=0
- <routers_pass> uci set ioman.dio1.value=1
Or you could create custom SMS rules, with commands to return/change status of the outputs. For this, you would need to login to gateway's WebUI, navigate to Services -> Mobile utilities -> SMS utilities. At the bottom of the page, add a new command with your preferred test and action set as Change I/O state. In an expanded configuration window select your input/output, select State to be set, add a timeout, if necessary.
Other than that, you would need to consult sensor's manual on how to convert read voltage/current value into actual pressure.