This is just some info on how to use the implant with a 10K thermistor in order to read temperature using one of the implant's analog input. It's already possible to measure temperature using a DS18B20 or DHT22 but in some cases, you might want to use a thermistor instead (e.g. pool sensor).
The simplest way is to connect the thermistor between one of the implant's input (IN1 or IN2) and ground and configure Input 2 - operating mode to be "Analog input with internal pull-up (Sensor Multilevel)".
Based on my measurements, the implant is pulling the input to 10V using a 17Kohms resistor. The 10V reference must be quite consistent from implant to implant but I would expect the pull-up resistor value to vary quite a bit so you might want to measure the one you have on your device. These values, combined with the thermistor's resistance to temperature relation is enough to come-up with an equation to transform the voltage reported by the implant to temperature.
See this for more info on thermistor equations. Using a simplified equation for the thermistor, we get the following equation for the temperature in degF calculated from the implant's measured voltage. You can copy and paste it in the "Temperature Equation" field of the Analog Input child device:
round(((1/(log(17000/10000*rawVoltage/(10-rawVoltage))/3950+1/(25+273.15))-273.15)*9/5+32)*100)/100
-Log is the natural logarithm
-17000 is the pull-up resistor value
-10 is the pull-up voltage value (10V, implant supply voltage must be 12V or higher)
-3950 is a constant associated with the thermistor
-10000 is the nominal thermistor resistance (10K thermistor)
-25 is the temperature corresponding to the thermistor nominal resistance (10K at 25degC in general)
You can adjust the thermistor constants (mostly the 3950 value, make sure the pull-up resistor value is correct first) ) to match your thermistor based on its specs or calibrate it at 2 or 3 different temperature points. This is a simplified equation that will work well if the temperature range is not too extreme. Use the more complicated equations from the link above if you need more accuracy.
