createTemperatureLookupMarlin.py: Add resolution comments and format for Marlin.

This commit is contained in:
David Forrest 2014-01-16 12:40:15 -05:00
parent 89a304fd98
commit 7216583b8b

View File

@ -54,9 +54,25 @@ class Thermistor:
self.c2 = c2 self.c2 = c2
self.c3 = c3 self.c3 = c3
def res(self,adc):
"Convert ADC reading into a resolution"
res = self.temp(adc)-self.temp(adc+1)
return res
def v(self,adc):
"Convert ADC reading into a Voltage"
v = adc * self.vadc / (1024 ) # convert the 10 bit ADC value to a voltage
return v
def r(self,adc):
"Convert ADC reading into a resistance in Ohms"
v = adc * self.vadc / (1024 ) # convert the 10 bit ADC value to a voltage
r = self.rp * v / (self.vcc - v) # resistance of thermistor
return r
def temp(self,adc): def temp(self,adc):
"Convert ADC reading into a temperature in Celcius" "Convert ADC reading into a temperature in Celcius"
v = adc * self.vadc / (1024 * 16) # convert the 10 bit ADC value to a voltage v = adc * self.vadc / (1024 ) # convert the 10 bit ADC value to a voltage
r = self.rp * v / (self.vcc - v) # resistance of thermistor r = self.rp * v / (self.vcc - v) # resistance of thermistor
lnr = log(r) lnr = log(r)
Tinv = self.c1 + (self.c2*lnr) + (self.c3*pow(lnr,3)) Tinv = self.c1 + (self.c2*lnr) + (self.c3*pow(lnr,3))
@ -67,7 +83,7 @@ class Thermistor:
y = (self.c1 - (1/(temp+273.15))) / (2*self.c3) y = (self.c1 - (1/(temp+273.15))) / (2*self.c3)
x = sqrt(pow(self.c2 / (3*self.c3),3) + pow(y,2)) x = sqrt(pow(self.c2 / (3*self.c3),3) + pow(y,2))
r = exp(pow(x-y,1.0/3) - pow(x+y,1.0/3)) # resistance of thermistor r = exp(pow(x-y,1.0/3) - pow(x+y,1.0/3)) # resistance of thermistor
return (r / (self.rp + r)) * (1024*16) return (r / (self.rp + r)) * (1024)
def main(argv): def main(argv):
@ -107,7 +123,7 @@ def main(argv):
elif opt == "--num-temps": elif opt == "--num-temps":
num_temps = int(arg) num_temps = int(arg)
max_adc = (1024 * 16) - 1 max_adc = (1024 ) - 1
min_temp = 0 min_temp = 0
max_temp = 350 max_temp = 350
increment = int(max_adc/(num_temps-1)); increment = int(max_adc/(num_temps-1));
@ -119,16 +135,16 @@ def main(argv):
print "// Thermistor lookup table for Marlin" print "// Thermistor lookup table for Marlin"
print "// ./createTemperatureLookup.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 "// ./createTemperatureLookup.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 "#define NUMTEMPS %s" % (len(temps)) print "//#define NUMTEMPS %s" % (len(temps))
print "short temptable[NUMTEMPS][2] = {" print "const short temptable[NUMTEMPS][2] PROGMEM = {"
counter = 0 counter = 0
for temp in temps: for temp in temps:
counter = counter +1 counter = counter +1
if counter == len(temps): if counter == len(temps):
print " {%s, %s}" % (int(t.adc(temp)), temp) print " {%s*OVERSAMPLENR, %s} // v=%s r=%s res=%s C/count" % (int(t.adc(temp)), temp, t.v(t.adc(temp)), t.r(t.adc(temp)),t.res(t.adc(temp)))
else: else:
print " {%s, %s}," % (int(t.adc(temp)), temp) print " {%s*OVERSAMPLENR, %s}, // v=%s r=%s res=%s C/count" % (int(t.adc(temp)), temp, t.v(t.adc(temp)), t.r(t.adc(temp)),t.res(t.adc(temp)))
print "};" print "};"
def usage(): def usage():