You can get data messages with the aR4 command.
An example response:
|Tr||Pt1000 (C = Celsius, F = Fahrenheit)|
|Ra||Aux rain accumulation (M = mm)|
|Sl||Ultrasonic level sensor (V = volts at input * gain)|
|Sr||Solar radiation (V = volts at input * gain)|
You can set the gain for Sr and Sl.