config: add BME280 documentation

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

2 files changed, 53 insertions, 0 deletions

diff --git a/config/example-extras.cfg b/config/example-extras.cfg
index 8ea42f0d..136ff1fa 100644
--- a/config/example-extras.cfg
+++ b/config/example-extras.cfg
@@ -821,6 +821,27 @@
 #   chips. The defaults for each parameter are next to the parameter
 #   name in the above list.
 
+# BME280 two wire interface (I2C) environmental sensor.  Note that this
+# sensor is not intended for use with extruders and heater beds, but rather
+# for montitoring ambient temperature (C), pressure (hPa), and relative
+# humidity. See sample-macros.cfg for a gcode_macro that may be used to report
+# pressure and humidity in addition to temperature.
+#[temperature_sensor my_sensor]
+# See the "temperature_sensor" section below for a description of its
+# parameters. The parameters below describe BME280 sensor parameters.
+#sensor_type:
+#   Must be "BME280"
+#i2c_address:
+#  Default is 118 (0x76).  Some BME280 sensors have an address of 119 (0x77).
+#i2c_mcu:
+#  MCU the sensor is connected to.  Default is the primary mcu.
+#i2c_bus:
+#  The I2C bus the sensor is connected to.  On some MCU platforms the default
+#  is bus 0.  On platforms without bus 0 this parameter is required.
+#i2c_speed:
+#  The I2C speed (in Hz) to use when communicating with the sensor.  Default
+#  is 100000.  On some MCUs changing this value has no effect.
+
 # Common temperature amplifiers. The following parameters are
 # available in heater sections that use one of these sensors.
 #[extruder]
diff --git a/config/sample-macros.cfg b/config/sample-macros.cfg
index 5f965fb1..3b92e34b 100644
--- a/config/sample-macros.cfg
+++ b/config/sample-macros.cfg
@@ -115,3 +115,35 @@ gcode:
     G91
     G1 E-50 F1000
     RESTORE_GCODE_STATE NAME=M600_state
+
+######################################################################
+# BME280 Environmental Sensor
+######################################################################
+
+# The macro below assumes you have a BME280 sensor_type defined in one
+# of the applicable sections in printer.cfg, such as:
+#
+#[temperature_sensor my_sensor]
+#sensor_type: BME280
+#gcode_id: AMB
+#
+# Note the format of the parameter SENSOR in the macro below.  The BME280
+# sensor status can be accessed using the format "bme280 <section_name>".
+# The example section above is named "my_sensor", thus the bme280 can be
+# queried as follows:
+#
+# QUERY_BME280 SENSOR='bme280 my_sensor'
+#
+# Since a default parameter is defined one could simply enter QUERY_BME280
+# as well.
+
+[gcode_macro QUERY_BME280]
+default_parameter_SENSOR: bme280 my_sensor
+gcode:
+    {printer.gcode.action_respond_info(
+        "Temperature: %.2f C\n"
+        "Pressure: %.2f hPa\n"
+        "Humidity: %.2f%%" % (
+            printer[SENSOR].temperature,
+            printer[SENSOR].pressure,
+            printer[SENSOR].humidity))}