Add thermistor support

adafruit_lc709203f.py

@@ -41,6 +41,9 @@
 LC709203F_CMD_INITRSOC = const(0x07)
 LC709203F_CMD_CELLVOLTAGE = const(0x09)
 LC709203F_CMD_CELLITE = const(0x0F)
+LC709203F_CMD_CELLTEMPERATURE = const(0x08)
+LC709203F_CMD_THERMISTORB = const(0x06)
+LC709203F_CMD_STATUSBIT = const(0x16)
 
 
 class CV:
@@ -121,6 +124,18 @@ def cell_percent(self):
         """Returns percentage of cell capacity"""
         return self._read_word(LC709203F_CMD_CELLITE) / 10
 
+    @property
+    def cell_temperature(self):
+        """Returns the temperature of the cell"""
+        return self._read_word(LC709203F_CMD_CELLTEMPERATURE) / 10 - 273.15
+
+    @cell_temperature.setter
+    def cell_temperature(self, value):
+        """Sets the temperature in the LC709203F"""
+        if self.thermistor_enable:
+            raise AttributeError("temperature can only be set in i2c mode")
+        self._write_word(LC709203F_CMD_CELLTEMPERATURE, int(value + 273.15) * 10)
+
     @property
     def ic_version(self):
         """Returns read-only chip version"""
@@ -159,6 +174,28 @@ def pack_size(self, size):
             raise AttributeError("pack_size must be a PackSize")
         self._write_word(LC709203F_CMD_APA, size)
 
+    @property
+    def thermistor_bconstant(self):
+        """Returns the thermistor B-constant"""
+        return self._read_word(LC709203F_CMD_THERMISTORB)
+
+    @thermistor_bconstant.setter
+    def thermistor_bconstant(self, bconstant):
+        """Sets the thermistor B-constant"""
+        self._write_word(LC709203F_CMD_THERMISTORB, bconstant)
+
+    @property
+    def thermistor_enable(self):
+        """Returns the current temperature source"""
+        return self._read_word(LC709203F_CMD_STATUSBIT)
+
+    @thermistor_enable.setter
+    def thermistor_enable(self, status):
+        """Sets the temperature source to Tsense"""
+        if not status in (True, False):
+            raise AttributeError("thermistor_enable must be True or False")
+        self._write_word(LC709203F_CMD_STATUSBIT, status)
+
     # pylint: disable=no-self-use
     def _generate_crc(self, data):
         """8-bit CRC algorithm for checking data"""

examples/lc709203f_thermistortest.py

@@ -0,0 +1,21 @@
+# SPDX-FileCopyrightText: 2021 Daniel Griswold
+#
+# SPDX-License-Identifier: MIT
+
+import time
+import board
+from adafruit_lc709203f import LC709203F
+
+print("LC709203F thermistor test")
+print("Make sure a thermistor is connected to the board!")
+
+sensor = LC709203F(board.I2C())
+
+# check your NTC thermistor datasheet for the appropriate B-Constant
+sensor.thermistor_bconstant = 3950
+sensor.thermistor_enable = True
+
+print("IC version:", hex(sensor.ic_version))
+while True:
+    print("Cell Temperature: %0.2f C" % (sensor.cell_temperature))
+    time.sleep(1)