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Author Topic: dual temp readings for 100k thermistors  (Read 1129 times)
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canada
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i am trying to make a temp logger for some testing on my project http://mike-mack.blogspot.com/2011/02/small-idea.html
i need it do read 2 100k thermistor inputs and put out a csv serial output,

i have not found examples to help me learn how to do it, so i would like some help.

i did find another project that dose have allot of the features i want but i am unable to figure out how to edit it to work with my setup
http://www.thebestcasescenario.com/forum/showthread.php?t=23490 and i also don't need it to be accurate past 1deg C

the temps i need to read up too are 220c and the value of the resistor on my divider circuit is 4.7k
i have gotten my circuit to work with one input with the code from this site, and the design from there too.
http://reprap.org/wiki/Temperature_Sensor_1_1
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UK
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There is some example code here for getting a temperature from a thermistor, in Project 13, here: http://www.arduinoevilgenius.com/projects. Go to the download page to get all the project sketches in a zip.

This is the crucial bit:
Code:
long a = analogRead(analogPin);
float temp = beta / (log(((1025.0 * resistance / a) - resistance) / resistance) + (beta / 298.0)) - 273.0;

Although, now I come to look at it again, it looks like it should simplify.

Anyway, it works, and the logger writes the temps to EEPROM and then on a command from the serial monitor it spews them all back up again.
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