micropython/drivers/sensor/pasco2: Cleanup and adding code comments.

Signed-off-by: NikhitaR-IFX <Nikhita.Rajasekhar@infineon.com>

micropython/drivers/sensor/pasco2/pasco2.py

@@ -2,16 +2,11 @@ from machine import I2C
 from utime import sleep, sleep_ms
 
 # Sensor Register Address Stack
-#_PASCO2_REG_PROD_ID        = const(0x00) # Product and revision ID register address
 _PASCO2_REG_SENS_STS       = const(0x01) # Sensor status register address  
 _PASCO2_REG_MEAS_RATE_H    = const(0x02) # Measurement period MSB configuration register address  
-#_PASCO2_REG_MEAS_RATE_L    = const(0x03) # Measurement period LSB register address  
 _PASCO2_REG_MEAS_CFG       = const(0x04) # Measurement mode configuration register address  
-_PASCO2_REG_CO2PPM_H       = const(0x05) # CO2 concentration result MSB register address  
-#_PASCO2_REG_CO2PPM_L       = const(0x06) # CO2 concentration result LSB register address  
-_PASCO2_REG_MEAS_STS       = const(0x07) # Measurement status register address  
-#_PASCO2_REG_INT_CFG        = const(0x08) # Interrupt pin configuration register address  
-#_PASCO2_REG_ALARM_TH_H     = const(0x09) # Alarm threshold MSB register address   
+_PASCO2_REG_CO2PPM_H       = const(0x05) # CO2 concentration result MSB register address   
+_PASCO2_REG_MEAS_STS       = const(0x07) # Measurement status register address    
 _PASCO2_REG_SENS_RST       = const(0x10) # Soft reset register address  
     
 #Error codes
@@ -25,34 +20,44 @@ i2c = I2C(0)
 
 class PASCO2:
     """IFX - XENSIV PAS CO2 sensor driver"""
-    regMap = { # RegAddr, Mask
-    'REG_SENS_STS_BITF_SENS_RDY' : [_PASCO2_REG_SENS_STS, 0x80],
-    'REG_MEAS_CFG_BITF_OP_MODE'  : [_PASCO2_REG_MEAS_CFG, 0x03],
+    # RegAddr, Mask, <Later extend with register access type, bit position etc.>
+    regMap = {
+    'REG_SENS_STS_BITF_SENS_RDY' : [_PASCO2_REG_SENS_STS, 0x80], # Sensor status bit
+    'REG_MEAS_CFG_BITF_OP_MODE'  : [_PASCO2_REG_MEAS_CFG, 0x03], # Operation Mode type bit
     'REG_MEAS_STS_BITF_DATA_RDY' : [_PASCO2_REG_MEAS_STS, 0x10], # Data ready status bit
-    'REG_CO2PPM_H_BITF_CO2_PPM_H': [_PASCO2_REG_CO2PPM_H, 0xFF],
+    'REG_CO2PPM_H_BITF_CO2_PPM_H': [_PASCO2_REG_CO2PPM_H, 0xFF], # Stored CO2 value bit
     }
     
     def __init__(self, bus, measInterval=10, sensorAddr=0x28):
+        """" Intialize the sensor and required dependencies """
         self.bus = bus
         self.sensorAddr = sensorAddr
         self.measInterval = measInterval
         self.softResetCode = b"\xa3"
         
     def _read_reg(self, regAddr, bytesToRead=1):
+        """ Internal function to read data from the sensor register and returns it raw """
         readVal = self.bus.readfrom_mem(self.sensorAddr, regAddr, bytesToRead)
         return readVal
     
     def _write_reg(self, regAddr, writeData):
+        """ Internal function to write data to sensor register """
         self.bus.writeto_mem(self.sensorAddr, regAddr, writeData)
     
     def _is_sensor_ready(self):
+        """ Helper function to check the sensor status """
         reg = self.regMap['REG_SENS_STS_BITF_SENS_RDY']
         return (self._read_reg(reg[addr])[0] & reg[mask])
     
     def _soft_reset(self):
+        """ Helper function to perform soft reset of the sensor """
         self._write_reg(_PASCO2_REG_SENS_RST, self.softResetCode)
         
     def _set_mode(self, mode):
+        """ Helper function to set the mode of sensor. Currently supported modes:
+        1. Idle
+        2. Continuous
+        """
         if mode == 'idle': modeVal = 0x00
         if mode == 'continuous': modeVal = 0x02
         
@@ -63,6 +68,7 @@ class PASCO2:
         
         
     def initialize(self):
+        """ Public function to initialize the sensor """
         try:
             # wait for sensor to be ready
             sensor_ready = self._is_sensor_ready()
@@ -80,7 +86,7 @@ class PASCO2:
 
             # reset operation mode to idle mode
             self._set_mode('idle')
-    
+
             # start continuous mode
             self._set_mode('continuous')   
     
@@ -90,6 +96,7 @@ class PASCO2:
             return _PASCO2_ERROR
     
     def getCO2Value(self):
+        """ Public function to get the CO2 value """
         while True:
             try: 
                 # get meas status