diff --git a/Marlin/scripts/createTemperatureLookupMarlin.py b/Marlin/scripts/createTemperatureLookupMarlin.py index 01c602dffa..372a5b5133 100755 --- a/Marlin/scripts/createTemperatureLookupMarlin.py +++ b/Marlin/scripts/createTemperatureLookupMarlin.py @@ -1,12 +1,8 @@ #!/usr/bin/python -# -# Creates a C code lookup table for doing ADC to temperature conversion -# on a microcontroller -# based on: http://hydraraptor.blogspot.com/2007/10/measuring-temperature-easy-way.html """Thermistor Value Lookup Table Generator Generates lookup to temperature values for use in a microcontroller in C format based on: -http://hydraraptor.blogspot.com/2007/10/measuring-temperature-easy-way.html +http://en.wikipedia.org/wiki/Steinhart-Hart_equation The main use is for Arduino programs that read data from the circuit board described here: http://make.rrrf.org/ts-1.0 @@ -19,7 +15,7 @@ Options: --t1=ttt:rrr low temperature temperature:resistance point (around 25C) --t2=ttt:rrr middle temperature temperature:resistance point (around 150C) --t3=ttt:rrr high temperature temperature:resistance point (around 250C) - --num-temps=... the number of temperature points to calculate (default: 20) + --num-temps=... the number of temperature points to calculate (default: 36) """ from math import * @@ -86,15 +82,15 @@ class Thermistor: return (r / (self.rp + r)) * (1024) def main(argv): - - rp = 4700; - t1 = 25; - r1 = 100000; - t2 = 150; - r2 = 1641.9; - t3 = 250; - r3 = 226.15; - num_temps = int(36); + "Default values" + t1 = 25 # low temperature in Kelvin (25 degC) + r1 = 100000 # resistance at low temperature (10 kOhm) + t2 = 150 # middle temperature in Kelvin (150 degC) + r2 = 1641.9 # resistance at middle temperature (1.6 KOhm) + t3 = 250 # high temperature in Kelvin (250 degC) + r3 = 226.15 # resistance at high temperature (226.15 Ohm) + rp = 4700; # pull-up resistor (4.7 kOhm) + num_temps = int(36); # number of entries for look-up table try: opts, args = getopt.getopt(argv, "h", ["help", "rp=", "t1=", "t2=", "t3=", "num-temps="]) @@ -102,7 +98,7 @@ def main(argv): print str(err) usage() sys.exit(2) - + for opt, arg in opts: if opt in ("-h", "--help"): usage() @@ -111,16 +107,16 @@ def main(argv): rp = int(arg) elif opt == "--t1": arg = arg.split(':') - t1 = float( arg[0]) - r1 = float( arg[1]) + t1 = float(arg[0]) + r1 = float(arg[1]) elif opt == "--t2": arg = arg.split(':') - t2 = float( arg[0]) - r2 = float( arg[1]) + t2 = float(arg[0]) + r2 = float(arg[1]) elif opt == "--t3": arg = arg.split(':') - t3 = float( arg[0]) - r3 = float( arg[1]) + t3 = float(arg[0]) + r3 = float(arg[1]) elif opt == "--num-temps": num_temps = int(arg) @@ -136,8 +132,9 @@ def main(argv): print "// Thermistor lookup table for Marlin" print "// ./createTemperatureLookupMarlin.py --rp=%s --t1=%s:%s --t2=%s:%s --t3=%s:%s --num-temps=%s" % (rp, t1, r1, t2, r2, t3, r3, num_temps) - print "// Steinhart-Hart Coefficients: %.15g, %.15g, %.15g " % (t.c1, t.c2, t.c3) - print "//#define NUMTEMPS %s" % (len(temps)) + print "// Steinhart-Hart Coefficients: a=%.15g, b=%.15g, c=%.15g " % (t.c1, t.c2, t.c3) + print + print "#define NUMTEMPS %s" % (len(temps)) print "const short temptable[NUMTEMPS][2] PROGMEM = {" counter = 0 @@ -148,7 +145,7 @@ def main(argv): else: print " {(short)(%.2f*OVERSAMPLENR), %s}, // v=%s r=%s res=%s C/count" % ((t.adc(temp)), temp, t.v(t.adc(temp)), t.r(t.adc(temp)),t.res(t.adc(temp))) print "};" - + def usage(): print __doc__