Can I programmatically set a new current temperature using the Nest API? Say, I build my own raspberry or Arduino based temperature sensor. Can that measure the current room temperature, and then set that as the current house temperature on Nest? Then of course Nest should continue operating as normal to reach whatever target temperature was already set.
In other words, can the Nest API override the measured current room temperature?
Are you trying to override the Nest's inbuilt thermometer? Or are you just trying to define the target temperature?
If 1, then you should set the Nest target very high, and keep measuring the ambient tmeperature until it reaches your desired temp, then set the Nest target very low - in this way you are effectively switching the heating on and off manually.
If 2, then you can just set the Nest target temperature as desired.
For either case, you will need to use the appropriate one of the following parameters (depending on your operating mode and your temperature scale of choice):