update calibration

demo.py

@@ -3,8 +3,8 @@ import powermon as pm
 from time import sleep
 
 sensors = [
-    [0x40, 0x08B6], # pink/blue: Pi
-    [0x44, 0x0B60]  # pink/pink: Solar panel
+    [0x40, 0.005, 0.00032, 0.696875],   # pink/blue: Pi;            5 mOhm; 0.32 mA/bit; 0.696875 mult
+    [0x44, 0.005, 0.00032, 0.91]        # pink/pink: Solar panel;   5 mOhm; 0.32 mA/bit; 0.91 mult
 ]
 
 solarmon = pm.PowerMon(sensors)

inachip.py

@@ -6,7 +6,6 @@ POWER_REG_ADDR = 0x03
 CURRENT_REG_ADDR = 0x04
 CAL_REG_ADDR = 0x05
 
-CURRENT_LSB = 0.00032
 VOLTAGE_LSB = 0.00125
 SHUNT_LSB = 0.0000025
 
@@ -16,14 +15,17 @@ class PowerData:
     current = 0.0
 
 class INA226:
-    def __init__(self, bus: smbus2.SMBus, addr: int, cal: int = 0):
+    # I2C Address, Shunt Resistor, Current LSB, Calibration Multiplier
+    def __init__(self, bus: smbus2.SMBus, addr: int, rshunt: int, clsb: float, cal: float = 1):
         self.addr = addr
+        self.rshunt = rshunt,
+        self.clsb = clsb,
         self.cal = cal
         self.bus = bus
         self.data = PowerData()
 
         # Initial calibration
-        self.calibrate(cal)
+        self.calibrate()
 
     def __readRegWord(self, reg: int) -> int:
         regWord = self.bus.read_word_data(self.addr, reg) & 0xFFFF
@@ -35,14 +37,15 @@ class INA226:
         self.bus.write_i2c_block_data(self.addr, reg, regBytes)
 
     # Calibrate current sensor
-    def calibrate(self, cal: int) -> None:
-        self.__writeRegWord(CAL_REG_ADDR, cal)
+    def calibrate(self) -> None:
+        calReg = int((0.00512 / (self.clsb * self.rshunt)) * self.cal)
+        self.__writeRegWord(CAL_REG_ADDR, calReg)
 
     # Retrieve power data from sensor
     def getData(self) -> PowerData:
         self.data.voltage = float(self.__readRegWord(VOLTAGE_REG_ADDR)) * VOLTAGE_LSB
-        self.data.power = float(self.__readRegWord(POWER_REG_ADDR)) * CURRENT_LSB * 25.0
-        self.data.current = float(self.__readRegWord(CURRENT_REG_ADDR)) * CURRENT_LSB
+        self.data.power = float(self.__readRegWord(POWER_REG_ADDR)) * self.clsb * 25.0
+        self.data.current = float(self.__readRegWord(CURRENT_REG_ADDR)) * self.clsb
         if (self.data.current > 20.96):
             self.data.current = 0.0
         return self.data

powermon.py

@@ -11,10 +11,7 @@ class PowerMon:
         try:
             ina = None
             for i in range(len(sensors)):
-                if type(list[i]) is int:
-                    ina = INA226(self.bus, sensors[i])
-                else:
-                    ina = INA226(self.bus, sensors[i][0], sensors[i][1])
+                ina = INA226(self.bus, sensors[i][0], sensors[i][1], sensors[i][2], sensors[i][3])
                 self.chipObjs.append(ina)
         except Exception as e:
             e.add_note("Initiating sensors failed")