From 3d65d3b61708d34e13a6c830c173721f4509a5ad Mon Sep 17 00:00:00 2001
From: Anton Tinyakov <anlorn@anlorn.com>
Date: Thu, 23 Apr 2020 21:50:59 -0400
Subject: [PATCH 1/2] Add functions to get/set baseline

---
 adafruit_ccs811.py | 31 +++++++++++++++++++++++++++++--
 1 file changed, 29 insertions(+), 2 deletions(-)

diff --git a/adafruit_ccs811.py b/adafruit_ccs811.py
index b00a083..fdd1ddc 100644
--- a/adafruit_ccs811.py
+++ b/adafruit_ccs811.py
@@ -44,13 +44,16 @@
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_CCS811.git"
 
+_BASELINE_PACKING_FORMAT = "<H"
+
 _ALG_RESULT_DATA = const(0x02)
 _RAW_DATA = const(0x03)
 _ENV_DATA = const(0x05)
 _NTC = const(0x06)
 _THRESHOLDS = const(0x10)
 
-# _BASELINE = 0x11
+_BASELINE = const(0x11)
+
 # _HW_ID = 0x20
 # _HW_VERSION = 0x21
 # _FW_BOOT_VERSION = 0x23
@@ -106,7 +109,6 @@ def __init__(self, i2c_bus, address=0x5A):
             raise RuntimeError(
                 "Device ID returned is not correct! Please check your wiring."
             )
-
         # try to start the app
         buf = bytearray(1)
         buf[0] = 0xF4
@@ -156,6 +158,31 @@ def _update_data(self):
             if self.error:
                 raise RuntimeError("Error:" + str(self.error_code))
 
+    @property
+    def baseline(self):
+        """
+        The function read and return the current baseline value.
+        The returned value is packed into an integer.
+        Later the same integer can be passed `set_baseline` function
+        in order to set a new baseline.
+        """
+        buf = bytearray(3)
+        buf[0] = _BASELINE
+        with self.i2c_device as i2c:
+            i2c.write_then_readinto(buf, buf, out_end=1, in_start=1)
+        return struct.unpack(_BASELINE_PACKING_FORMAT, buf[1:])[0]
+
+    def set_baseline(self, baseline_int):
+        """
+        The function lets you set a new baseline. As an argument accepts
+        integer which represents packed baseline 2 bytes value.
+        """
+        buf = bytearray(3)
+        buf[0] = _BASELINE
+        struct.pack_into(_BASELINE_PACKING_FORMAT, buf, 1, baseline_int)
+        with self.i2c_device as i2c:
+            i2c.write(buf)
+
     @property
     def tvoc(self):  # pylint: disable=invalid-name
         """Total Volatile Organic Compound in parts per billion."""

From 7279d2c075ca61f805dfb48c527429bb4eaf4804 Mon Sep 17 00:00:00 2001
From: Anton Tinyakov <anlorn@anlorn.com>
Date: Sat, 25 Apr 2020 00:25:39 -0400
Subject: [PATCH 2/2] Add a property setter for baseline

---
 adafruit_ccs811.py | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/adafruit_ccs811.py b/adafruit_ccs811.py
index fdd1ddc..c922a25 100644
--- a/adafruit_ccs811.py
+++ b/adafruit_ccs811.py
@@ -44,7 +44,6 @@
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_CCS811.git"
 
-_BASELINE_PACKING_FORMAT = "<H"
 
 _ALG_RESULT_DATA = const(0x02)
 _RAW_DATA = const(0x03)
@@ -161,25 +160,26 @@ def _update_data(self):
     @property
     def baseline(self):
         """
-        The function read and return the current baseline value.
+        The propery reads and returns the current baseline value.
         The returned value is packed into an integer.
-        Later the same integer can be passed `set_baseline` function
-        in order to set a new baseline.
+        Later the same integer can be used in order
+        to set a new baseline.
         """
         buf = bytearray(3)
         buf[0] = _BASELINE
         with self.i2c_device as i2c:
             i2c.write_then_readinto(buf, buf, out_end=1, in_start=1)
-        return struct.unpack(_BASELINE_PACKING_FORMAT, buf[1:])[0]
+        return struct.unpack("<H", buf[1:])[0]
 
-    def set_baseline(self, baseline_int):
+    @baseline.setter
+    def baseline(self, baseline_int):
         """
-        The function lets you set a new baseline. As an argument accepts
+        The property lets you set a new baseline. As a value accepts
         integer which represents packed baseline 2 bytes value.
         """
         buf = bytearray(3)
         buf[0] = _BASELINE
-        struct.pack_into(_BASELINE_PACKING_FORMAT, buf, 1, baseline_int)
+        struct.pack_into("<H", buf, 1, baseline_int)
         with self.i2c_device as i2c:
             i2c.write(buf)