Update eCO2 and TVOC properties to match sensor standard (closes #1).

https://github.com/adafruit/circuitpython/blob/master/docs/design_guide.rst#sensor-properties-and-units

Author: process1183

README.rst

@@ -60,8 +60,8 @@ To read from the sensor:
 
 .. code-block:: python
 
-    co2eq, tvoc = sgp30.iaq_measure()
-    print("CO2eq = %d ppm \t TVOC = %d ppb" % (co2eq, tvoc))
+    eCO2, TVOC = sgp30.iaq_measure()
+    print("eCO2 = %d ppm \t TVOC = %d ppb" % (eCO2, TVOC))
 
 
 Contributing

adafruit_sgp30.py

@@ -77,25 +77,29 @@ def __init__(self, i2c, address=_SGP30_DEFAULT_I2C_ADDR):
 
 
     @property
-    def tvoc(self):
+    # pylint: disable=invalid-name
+    def TVOC(self):
         """Total Volatile Organic Compound in parts per billion."""
         return self.iaq_measure()[1]
 
 
     @property
-    def baseline_tvoc(self):
+    # pylint: disable=invalid-name
+    def baseline_TVOC(self):
         """Total Volatile Organic Compound baseline value"""
         return self.get_iaq_baseline()[1]
 
 
     @property
-    def co2eq(self):
+    # pylint: disable=invalid-name
+    def eCO2(self):
         """Carbon Dioxide Equivalent in parts per million"""
         return self.iaq_measure()[0]
 
 
     @property
-    def baseline_co2eq(self):
+    # pylint: disable=invalid-name
+    def baseline_eCO2(self):
         """Carbon Dioxide Equivalent baseline value"""
         return self.get_iaq_baseline()[0]
 
@@ -106,22 +110,21 @@ def iaq_init(self):
         self._run_profile(["iaq_init", [0x20, 0x03], 0, 0.01])
 
     def iaq_measure(self):
-        """Measure the CO2eq and TVOC"""
+        """Measure the eCO2 and TVOC"""
         # name, command, signals, delay
         return self._run_profile(["iaq_measure", [0x20, 0x08], 2, 0.05])
 
     def get_iaq_baseline(self):
-        """Retreive the IAQ algorithm baseline for CO2eq and TVOC"""
+        """Retreive the IAQ algorithm baseline for eCO2 and TVOC"""
         # name, command, signals, delay
         return self._run_profile(["iaq_get_baseline", [0x20, 0x15], 2, 0.01])
 
-
-    def set_iaq_baseline(self, co2eq, tvoc):
-        """Set the previously recorded IAQ algorithm baseline for CO2eq and TVOC"""
-        if co2eq == 0 and tvoc == 0:
+    def set_iaq_baseline(self, eCO2, TVOC): # pylint: disable=invalid-name
+        """Set the previously recorded IAQ algorithm baseline for eCO2 and TVOC"""
+        if eCO2 == 0 and TVOC == 0:
             raise RuntimeError('Invalid baseline')
         buffer = []
-        for value in [tvoc, co2eq]:
+        for value in [TVOC, eCO2]:
             arr = [value >> 8, value & 0xFF]
             arr.append(self._generate_crc(arr))
             buffer += arr

examples/sgp30_simpletest.py

@@ -18,10 +18,10 @@
 elapsed_sec = 0
 
 while True:
-    print("co2eq = %d ppm \t tvoc = %d ppb" % (sgp30.co2eq, sgp30.tvoc))
+    print("eCO2 = %d ppm \t TVOC = %d ppb" % (sgp30.eCO2, sgp30.TVOC))
     time.sleep(1)
     elapsed_sec += 1
     if elapsed_sec > 10:
         elapsed_sec = 0
-        print("**** Baseline values: co2eq = 0x%x, tvoc = 0x%x"
-              % (sgp30.baseline_co2eq, sgp30.baseline_tvoc))
+        print("**** Baseline values: eCO2 = 0x%x, TVOC = 0x%x"
+              % (sgp30.baseline_eCO2, sgp30.baseline_TVOC))