Beginner cuestion items modbus extract data

Hello

Sorry for bad english.

Demo.tems:
Number Weather_Temperature "Temperatura de fuera [%+.2f °C]" <temperature> (Weather_Chart) { modbus="slave1:1" }

My Arduino modbus send “2532” for see 25,32ºC. I must 2532 divide /100. But (modbus=“slave1:1”) /100 don’t work.
In .rules try var Number X= (modbus=“slave1:1”) don’t work. String, int, float, etc don’t work. Integer.parseInt(modbus=“slave1:1”) also don’t work.
Nothing work…
I do not understand modbus=“slave1:1”

Thanks