Fixes and notes for QMP6988 sensor

denko-rb · Oct 8, 2023 · a8ef1c7 · a8ef1c7
1 parent 89ede47
commit a8ef1c7
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Showing 3 changed files with 18 additions and 9 deletions.
diff --git a/examples/advanced/m5_env.rb b/examples/advanced/m5_env.rb
@@ -16,8 +16,12 @@
 qmp.pressure_samples = 16
 qmp.iir_coefficient = 2
 
+# Buggy on ESP32-S3 in forced mode. Data registers return zeroes on all but first read.
+# Can't recreate on ESP32 V1, AVR or SAMD21. Put it in contiuous mode just in case.
+qmp.continuous_mode
+
 # Get the shared #print_tph_reading method to print readings neatly.
-require_relative 'neat_tph_readings'
+require_relative '../sensor/neat_tph_readings'
 
 # How many degrees C the two temperature values can differ by before a warning.
 TOLERANCE = 0.50

diff --git a/examples/sensor/qmp6988.rb b/examples/sensor/qmp6988.rb
@@ -28,9 +28,13 @@
 sensor.pressure_samples = 16
 sensor.iir_coefficient = 2
 
+#
 # Change mode (default: forced_mode)
+#
+# Buggy on ESP32S3 in forced mode. Data registers return zeroes on all but first read.
+# Can't recreate on ESP32 V1, AVR or SAMD21. Put it in contiuous mode just in case.
+sensor.continuous_mode
 # sensor.forced_mode
-# sensor.continuous_mode
 
 #
 # Set standby time (between measurements) for continuous mode only:

diff --git a/lib/denko/sensor/qmp6988.rb b/lib/denko/sensor/qmp6988.rb
@@ -103,12 +103,6 @@ def reset
         sleep UPDATE_TIME
       end
 
-      def get_config_registers
-        i2c_read(IIR_REGISTER, 5)
-        sleep 0.001 while !@registers
-        @registers
-      end
-
       def iir_coefficient=(coeff)
         raise ArgumentError, "invalid IIR coefficient: #{coeff}" unless IIR_COEFFICIENTS.keys.include? coeff
         i2c_write [IIR_REGISTER, IIR_COEFFICIENTS[coeff]]
@@ -160,7 +154,7 @@ def forced_mode
       end
 
       def continuous_mode
-        @ctrl_meas_register = (@ctrl_meas_register & 0b11111100) | NORMAL_MDOE
+        @ctrl_meas_register = (@ctrl_meas_register & 0b11111100) | NORMAL_MODE
         i2c_write [CTRL_MEAS_REGISTER, @ctrl_meas_register]
         @forced_mode = false
         sleep UPDATE_TIME
@@ -233,6 +227,13 @@ def update_state(reading)
         end
       end
 
+      def get_config_registers
+        @registers = {}
+        i2c_read(IIR_REGISTER, CONFIG_LENGTH)
+        sleep 0.001 while @registers.empty?
+        @registers
+      end
+
       def process_config(bytes)
         @registers = { f1: bytes[0], f2: bytes[1], f3: bytes[2], f4: bytes[3], f5: bytes[4] }
       end