From 2d191768caba4f53438254300a426285950cfa82 Mon Sep 17 00:00:00 2001 From: Markus Hitter Date: Mon, 20 Apr 2015 16:32:19 +0200 Subject: [PATCH] createTemperatureLookup.py: deal with precision limitation on R0. Inserting a dummy value is better than risking an exception with failure to write a thermistor table at all. Happens when for one of the usual thermistors accidently a nominal resistance of 1000k instead of 100k is used. --- createTemperatureLookup.py | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/createTemperatureLookup.py b/createTemperatureLookup.py index 6ee9741..c75dd64 100755 --- a/createTemperatureLookup.py +++ b/createTemperatureLookup.py @@ -62,7 +62,10 @@ class Thermistor: def temp(self,adc): "Convert ADC reading into a temperature in Celcius" v = adc * self.vadc / 1024 # convert the 10 bit ADC value to a voltage - r = self.rs * v / (self.vs - v) # resistance of thermistor + if (self.vs - v): # can be zero due to accuracy limitations + r = self.rs * v / (self.vs - v) # resistance of thermistor + else: + r = self.r0 * 10 # dummy value try: return (self.beta / log(r / self.k)) - 273.15 # temperature except: