- make class of it

git-svn-id: http://moon:8086/svn/projects/HendiControl@189 fda53097-d464-4ada-af97-ba876c37ca34

Control/brewpi/max31865.py

@@ -1,40 +1,51 @@
 #!/usr/bin/python
 
 import spidev
-import time
-import os
 
-# Open SPI bus
-spi = spidev.SpiDev()
-spi.open(0,0)
-spi.max_speed_hz=100000
-spi.mode = 0b01
 
-def read_reg(addr):
-	reg = spi.xfer([addr, 0xFF]);
+class Max31865():
+	def __init__(self):
+		# Open SPI bus
+		self.spi = spidev.SpiDev()
+		self.spi.open(0, 0)
+		self.spi.max_speed_hz = 100000
+		self.spi.mode = 0b01
+		self.write_reg(0x00, 0xA3)
+
+	def read_reg(self, addr):
+		reg = self.spi.xfer([addr, 0xFF])
 
 		return reg[1]
 
-def write_reg(addr, data):
-	spi.xfer([addr+0x80, data]);
+	def write_reg(self, addr, data):
+		self.spi.xfer([addr+0x80, data])
 
-def read_digits():
-	msb = read_reg(0x01)
-	lsb = read_reg(0x02)
+	def read_digits(self):
+		msb = self.read_reg(0x01)
+		lsb = self.read_reg(0x02)
 		digits = float(256*msb + lsb)/2
 
 		return digits
 
-def calc_R(Rref, digits):
+	def getTemperature(self):
+		digits = self.read_digits()
+		R = max31865.calc_R(430, digits)
+		T = max31865.vanDusen_temp(R)
+		print("R={:.3f} Ohm, T={:.2f} degC".format(R, T))
+		return T
+
+	@staticmethod
+	def calc_R(Rref, digits):
 		k = digits / 8192 / 4
 		R = k*Rref
 
 		return R
 
-def vanDusenLut (R0, Tmin, Tmax, dT):
-	a = +3.90830e-03;
-	b = -5.77500e-07;
-	c = -4.18301e-12;
+	@staticmethod
+	def vanDusenLut (R0, Tmin, Tmax, dT):
+		a = +3.90830e-03
+		b = -5.77500e-07
+		c = -4.18301e-12
 
 		Rv = []
 		Tv = []
@@ -43,7 +54,7 @@ def vanDusenLut (R0, Tmin, Tmax, dT):
 			R = R0*(1 + a*T + b*T**2)
 
 			if T < 0.0:
-			R += R0*c*(T - 100)*T**3;
+				R += R0*c*(T - 100)*T**3
 
 			Rv.append(R)
 			Tv.append(T)
@@ -51,8 +62,9 @@ def vanDusenLut (R0, Tmin, Tmax, dT):
 
 		return Rv, Tv
 
-def vanDusen_temp(Rmeas):
-	RLut, TLut = vanDusenLut(100, -150, +500, 1.0)
+	@staticmethod
+	def vanDusen_temp(Rmeas):
+		RLut, TLut = Max31865.vanDusenLut(100, -150, +500, 1.0)
 
 		# Find candidate
 		i = 0
@@ -75,15 +87,15 @@ def vanDusen_temp(Rmeas):
 
 		return T
 
+
 # Main
-write_reg(0x00, 0xA3)
-digits = read_digits()
-R = calc_R(430, digits)
-T = vanDusen_temp(R)
-print("R={:.3f} Ohm, T={:.2f} degC".format(R, T))
+if __name__ == '__main__':
 
-for i in range (0, 8):
-	print("Reg[0x{}]: 0x{:02X}".format(i, read_reg(i)))
+	max31865 = Max31865()
+	for i in range (0, 8):
+		print("Reg[0x{}]: 0x{:02X}".format(i, max31865.read_reg(i)))
 
-print("End of program")
+	max31865.getTemperature()
+
+	print("End of program")