Add QMC5883L Sensor + Improvements to HMC5883L (#671)

* Add QMC5883L and Updated HMC5883L

* add tests

* changed to oversampling

* fix pylint

* fix private method

* typo fix

* fix protected method

* Clean up code and PR recomendations

* fix tests

* remote file

* fix qmc oversampling unit

* Remove hmc5883l config logging

Either the units are converted to the user values like 1x, 8x oversampling or not printed at all. Printing the machine-value of these is only confusing users.

* Changes for validate_enum

Move stuff that can be done beforehand out of the bound function, use text_type for py2/3 compatability.

* Remove unused constant

* Remove duplicate tests

* Repeat remove config print

* remove changes to test2 since bin is to large

* Add comment to HMC5583L


Co-authored-by: Timothy Purchas <timothy@TPF.local>
Co-authored-by: Otto Winter <otto@otto-winter.com>

esphome/components/hmc5883l/hmc5883l.cpp

@@ -38,12 +38,9 @@ void HMC5883LComponent::setup() {
   }
 
   uint8_t config_a = 0;
-  // 0b0xx00000 << 5 Sample Averaging - 0b00=1 sample, 0b11=8 samples
+  config_a |= this->oversampling_ << 5;
-  config_a |= 0b01100000;
+  config_a |= this->datarate_ << 2;
-  // 0b000xxx00 << 2 Data Output Rate - 0b100=15Hz
+  config_a |= 0b0 << 0;  // Measurement Mode: Normal(high impedance on load)
-  config_a |= 0b00010000;
-  // 0b000000xx << 0 Measurement Mode - 0b00=high impedance on load
-  config_a |= 0b00000000;
   if (!this->write_byte(HMC5883L_REGISTER_CONFIG_A, config_a)) {
     this->error_code_ = COMMUNICATION_FAILED;
     this->mark_failed();
@@ -61,7 +58,6 @@ void HMC5883LComponent::setup() {
   uint8_t mode = 0;
   // Continuous Measurement Mode
   mode |= 0b00;
-
   if (!this->write_byte(HMC5883L_REGISTER_MODE, mode)) {
     this->error_code_ = COMMUNICATION_FAILED;
     this->mark_failed();

esphome/components/hmc5883l/hmc5883l.h

@@ -7,6 +7,23 @@
 namespace esphome {
 namespace hmc5883l {
 
+enum HMC5883LOversampling {
+  HMC5883L_OVERSAMPLING_1 = 0b000,
+  HMC5883L_OVERSAMPLING_2 = 0b001,
+  HMC5883L_OVERSAMPLING_4 = 0b010,
+  HMC5883L_OVERSAMPLING_8 = 0b011,
+};
+
+enum HMC5883LDatarate {
+  HMC5883L_DATARATE_0_75_HZ = 0b000,
+  HMC5883L_DATARATE_1_5_HZ = 0b001,
+  HMC5883L_DATARATE_3_0_HZ = 0b010,
+  HMC5883L_DATARATE_7_5_HZ = 0b011,
+  HMC5883L_DATARATE_15_0_HZ = 0b100,
+  HMC5883L_DATARATE_30_0_HZ = 0b101,
+  HMC5883L_DATARATE_75_0_HZ = 0b110,
+};
+
 enum HMC5883LRange {
   HMC5883L_RANGE_88_UT = 0b000,
   HMC5883L_RANGE_130_UT = 0b001,
@@ -25,6 +42,8 @@ class HMC5883LComponent : public PollingComponent, public i2c::I2CDevice {
   float get_setup_priority() const override;
   void update() override;
 
+  void set_oversampling(HMC5883LOversampling oversampling) { oversampling_ = oversampling; }
+  void set_datarate(HMC5883LDatarate datarate) { datarate_ = datarate; }
   void set_range(HMC5883LRange range) { range_ = range; }
   void set_x_sensor(sensor::Sensor *x_sensor) { x_sensor_ = x_sensor; }
   void set_y_sensor(sensor::Sensor *y_sensor) { y_sensor_ = y_sensor; }
@@ -32,6 +51,8 @@ class HMC5883LComponent : public PollingComponent, public i2c::I2CDevice {
   void set_heading_sensor(sensor::Sensor *heading_sensor) { heading_sensor_ = heading_sensor; }
 
  protected:
+  HMC5883LOversampling oversampling_{HMC5883L_OVERSAMPLING_1};
+  HMC5883LDatarate datarate_{HMC5883L_DATARATE_15_0_HZ};
   HMC5883LRange range_{HMC5883L_RANGE_130_UT};
   sensor::Sensor *x_sensor_;
   sensor::Sensor *y_sensor_;

esphome/components/hmc5883l/sensor.py

@@ -2,8 +2,10 @@
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.components import i2c, sensor
-from esphome.const import CONF_ADDRESS, CONF_ID, CONF_RANGE, ICON_MAGNET, UNIT_MICROTESLA, \
+from esphome.const import (CONF_ADDRESS, CONF_ID, CONF_OVERSAMPLING, CONF_RANGE, ICON_MAGNET,
-    UNIT_DEGREES, ICON_SCREEN_ROTATION
+                           UNIT_MICROTESLA, UNIT_DEGREES, ICON_SCREEN_ROTATION,
+                           CONF_UPDATE_INTERVAL)
+from esphome.py_compat import text_type
 
 DEPENDENCIES = ['i2c']
 
@@ -16,6 +18,25 @@ CONF_HEADING = 'heading'
 
 HMC5883LComponent = hmc5883l_ns.class_('HMC5883LComponent', cg.PollingComponent, i2c.I2CDevice)
 
+HMC5883LOversampling = hmc5883l_ns.enum('HMC5883LOversampling')
+HMC5883LOversamplings = {
+    1: HMC5883LOversampling.HMC5883L_OVERSAMPLING_1,
+    2: HMC5883LOversampling.HMC5883L_OVERSAMPLING_2,
+    4: HMC5883LOversampling.HMC5883L_OVERSAMPLING_4,
+    8: HMC5883LOversampling.HMC5883L_OVERSAMPLING_8,
+}
+
+HMC5883LDatarate = hmc5883l_ns.enum('HMC5883LDatarate')
+HMC5883LDatarates = {
+    0.75: HMC5883LDatarate.HMC5883L_DATARATE_0_75_HZ,
+    1.5: HMC5883LDatarate.HMC5883L_DATARATE_1_5_HZ,
+    3.0: HMC5883LDatarate.HMC5883L_DATARATE_3_0_HZ,
+    7.5: HMC5883LDatarate.HMC5883L_DATARATE_7_5_HZ,
+    15: HMC5883LDatarate.HMC5883L_DATARATE_15_0_HZ,
+    30: HMC5883LDatarate.HMC5883L_DATARATE_30_0_HZ,
+    75: HMC5883LDatarate.HMC5883L_DATARATE_75_0_HZ,
+}
+
 HMC5883LRange = hmc5883l_ns.enum('HMC5883LRange')
 HMC5883L_RANGES = {
     88: HMC5883LRange.HMC5883L_RANGE_88_UT,
@@ -29,11 +50,21 @@ HMC5883L_RANGES = {
 }
 
 
-def validate_range(value):
+def validate_enum(enum_values, units=None, int=True):
-    value = cv.string(value)
+    _units = []
-    if value.endswith(u'µT') or value.endswith('uT'):
+    if units is not None:
-        value = value[:-2]
+        _units = units if isinstance(units, list) else [units]
-    return cv.enum(HMC5883L_RANGES, int=True)(value)
+        _units = [text_type(x) for x in _units]
+    enum_bound = cv.enum(enum_values, int=int)
+
+    def validate_enum_bound(value):
+        value = cv.string(value)
+        for unit in _units:
+            if value.endswith(unit):
+                value = value[:-len(unit)]
+                break
+        return enum_bound(value)
+    return validate_enum_bound
 
 
 field_strength_schema = sensor.sensor_schema(UNIT_MICROTESLA, ICON_MAGNET, 1)
@@ -42,19 +73,31 @@ heading_schema = sensor.sensor_schema(UNIT_DEGREES, ICON_SCREEN_ROTATION, 1)
 CONFIG_SCHEMA = cv.Schema({
     cv.GenerateID(): cv.declare_id(HMC5883LComponent),
     cv.Optional(CONF_ADDRESS): cv.i2c_address,
+    cv.Optional(CONF_OVERSAMPLING, default='1x'): validate_enum(HMC5883LOversamplings, units="x"),
+    cv.Optional(CONF_RANGE, default=u'130µT'): validate_enum(HMC5883L_RANGES, units=["uT", u"µT"]),
     cv.Optional(CONF_FIELD_STRENGTH_X): field_strength_schema,
     cv.Optional(CONF_FIELD_STRENGTH_Y): field_strength_schema,
     cv.Optional(CONF_FIELD_STRENGTH_Z): field_strength_schema,
     cv.Optional(CONF_HEADING): heading_schema,
-    cv.Optional(CONF_RANGE, default='130uT'): validate_range,
 }).extend(cv.polling_component_schema('60s')).extend(i2c.i2c_device_schema(0x1E))
 
 
+def auto_data_rate(config):
+    interval_sec = config[CONF_UPDATE_INTERVAL].seconds
+    interval_hz = 1.0/interval_sec
+    for datarate in sorted(HMC5883LDatarates.keys()):
+        if float(datarate) >= interval_hz:
+            return HMC5883LDatarates[datarate]
+    return HMC5883LDatarates[75]
+
+
 def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     yield cg.register_component(var, config)
     yield i2c.register_i2c_device(var, config)
 
+    cg.add(var.set_oversampling(config[CONF_OVERSAMPLING]))
+    cg.add(var.set_datarate(auto_data_rate(config)))
     cg.add(var.set_range(config[CONF_RANGE]))
     if CONF_FIELD_STRENGTH_X in config:
         sens = yield sensor.new_sensor(config[CONF_FIELD_STRENGTH_X])

esphome/components/qmc5883l/qmc5883l.cpp

@@ -0,0 +1,124 @@
+#include "qmc5883l.h"
+#include "esphome/core/log.h"
+
+namespace esphome {
+namespace qmc5883l {
+
+static const char *TAG = "qmc5883l";
+static const uint8_t QMC5883L_ADDRESS = 0x0D;
+
+static const uint8_t QMC5883L_REGISTER_DATA_X_LSB = 0x00;
+static const uint8_t QMC5883L_REGISTER_DATA_X_MSB = 0x01;
+static const uint8_t QMC5883L_REGISTER_DATA_Y_LSB = 0x02;
+static const uint8_t QMC5883L_REGISTER_DATA_Y_MSB = 0x03;
+static const uint8_t QMC5883L_REGISTER_DATA_Z_LSB = 0x04;
+static const uint8_t QMC5883L_REGISTER_DATA_Z_MSB = 0x05;
+static const uint8_t QMC5883L_REGISTER_STATUS = 0x06;
+static const uint8_t QMC5883L_REGISTER_TEMPERATURE_LSB = 0x07;
+static const uint8_t QMC5883L_REGISTER_TEMPERATURE_MSB = 0x08;
+static const uint8_t QMC5883L_REGISTER_CONTROL_1 = 0x09;
+static const uint8_t QMC5883L_REGISTER_CONTROL_2 = 0x0A;
+static const uint8_t QMC5883L_REGISTER_PERIOD = 0x0B;
+
+void QMC5883LComponent::setup() {
+  ESP_LOGCONFIG(TAG, "Setting up QMC5883L...");
+  // Soft Reset
+  if (!this->write_byte(QMC5883L_REGISTER_CONTROL_2, 1 << 7)) {
+    this->error_code_ = COMMUNICATION_FAILED;
+    this->mark_failed();
+    return;
+  }
+  delay(10);
+
+  uint8_t control_1 = 0;
+  control_1 |= 0b01 << 0;  // MODE (Mode) -> 0b00=standby, 0b01=continuous
+  control_1 |= this->datarate_ << 2;
+  control_1 |= this->range_ << 4;
+  control_1 |= this->oversampling_ << 6;
+  if (!this->write_byte(QMC5883L_REGISTER_CONTROL_1, control_1)) {
+    this->error_code_ = COMMUNICATION_FAILED;
+    this->mark_failed();
+    return;
+  }
+
+  uint8_t control_2 = 0;
+  control_2 |= 0b0 << 7;  // SOFT_RST (Soft Reset) -> 0b00=disabled, 0b01=enabled
+  control_2 |= 0b0 << 6;  // ROL_PNT (Pointer Roll Over) -> 0b00=disabled, 0b01=enabled
+  control_2 |= 0b0 << 0;  // INT_ENB (Interrupt) -> 0b00=disabled, 0b01=enabled
+  if (!this->write_byte(QMC5883L_REGISTER_CONTROL_2, control_2)) {
+    this->error_code_ = COMMUNICATION_FAILED;
+    this->mark_failed();
+    return;
+  }
+
+  uint8_t period = 0x01;  // recommended value
+  if (!this->write_byte(QMC5883L_REGISTER_PERIOD, period)) {
+    this->error_code_ = COMMUNICATION_FAILED;
+    this->mark_failed();
+    return;
+  }
+}
+void QMC5883LComponent::dump_config() {
+  ESP_LOGCONFIG(TAG, "QMC5883L:");
+  LOG_I2C_DEVICE(this);
+  if (this->error_code_ == COMMUNICATION_FAILED) {
+    ESP_LOGE(TAG, "Communication with QMC5883L failed!");
+  }
+  LOG_UPDATE_INTERVAL(this);
+
+  LOG_SENSOR("  ", "X Axis", this->x_sensor_);
+  LOG_SENSOR("  ", "Y Axis", this->y_sensor_);
+  LOG_SENSOR("  ", "Z Axis", this->z_sensor_);
+  LOG_SENSOR("  ", "Heading", this->heading_sensor_);
+}
+float QMC5883LComponent::get_setup_priority() const { return setup_priority::DATA; }
+void QMC5883LComponent::update() {
+  uint8_t status = false;
+  this->read_byte(QMC5883L_REGISTER_STATUS, &status);
+
+  uint16_t raw_x, raw_y, raw_z;
+  if (!this->read_byte_16_(QMC5883L_REGISTER_DATA_X_LSB, &raw_x) ||
+      !this->read_byte_16_(QMC5883L_REGISTER_DATA_Y_LSB, &raw_y) ||
+      !this->read_byte_16_(QMC5883L_REGISTER_DATA_Z_LSB, &raw_z)) {
+    this->status_set_warning();
+    return;
+  }
+
+  float mg_per_bit;
+  switch (this->range_) {
+    case QMC5883L_RANGE_200_UT:
+      mg_per_bit = 0.0833f;
+      break;
+    case QMC5883L_RANGE_800_UT:
+      mg_per_bit = 0.333f;
+      break;
+    default:
+      mg_per_bit = NAN;
+  }
+
+  // in µT
+  const float x = int16_t(raw_x) * mg_per_bit * 0.1f;
+  const float y = int16_t(raw_y) * mg_per_bit * 0.1f;
+  const float z = int16_t(raw_z) * mg_per_bit * 0.1f;
+
+  float heading = atan2f(0.0f - x, y) * 180.0f / M_PI;
+  ESP_LOGD(TAG, "Got x=%0.02fµT y=%0.02fµT z=%0.02fµT heading=%0.01f° status=%u", x, y, z, heading, status);
+
+  if (this->x_sensor_ != nullptr)
+    this->x_sensor_->publish_state(x);
+  if (this->y_sensor_ != nullptr)
+    this->y_sensor_->publish_state(y);
+  if (this->z_sensor_ != nullptr)
+    this->z_sensor_->publish_state(z);
+  if (this->heading_sensor_ != nullptr)
+    this->heading_sensor_->publish_state(heading);
+}
+
+bool QMC5883LComponent::read_byte_16_(uint8_t a_register, uint16_t *data) {
+  bool success = this->read_byte_16(a_register, data);
+  *data = (*data & 0x00FF) << 8 | (*data & 0xFF00) >> 8;  // Flip Byte oder, LSB first;
+  return success;
+}
+
+}  // namespace qmc5883l
+}  // namespace esphome

esphome/components/qmc5883l/qmc5883l.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/sensor/sensor.h"
+#include "esphome/components/i2c/i2c.h"
+
+namespace esphome {
+namespace qmc5883l {
+
+enum QMC5883LDatarate {
+  QMC5883L_DATARATE_10_HZ = 0b00,
+  QMC5883L_DATARATE_50_HZ = 0b01,
+  QMC5883L_DATARATE_100_HZ = 0b10,
+  QMC5883L_DATARATE_200_HZ = 0b11,
+};
+
+enum QMC5883LRange {
+  QMC5883L_RANGE_200_UT = 0b00,
+  QMC5883L_RANGE_800_UT = 0b01,
+};
+
+enum QMC5883LOversampling {
+  QMC5883L_SAMPLING_512 = 0b00,
+  QMC5883L_SAMPLING_256 = 0b01,
+  QMC5883L_SAMPLING_128 = 0b10,
+  QMC5883L_SAMPLING_64 = 0b11,
+};
+
+class QMC5883LComponent : public PollingComponent, public i2c::I2CDevice {
+ public:
+  void setup() override;
+  void dump_config() override;
+  float get_setup_priority() const override;
+  void update() override;
+
+  void set_datarate(QMC5883LDatarate datarate) { datarate_ = datarate; }
+  void set_range(QMC5883LRange range) { range_ = range; }
+  void set_oversampling(QMC5883LOversampling oversampling) { oversampling_ = oversampling; }
+  void set_x_sensor(sensor::Sensor *x_sensor) { x_sensor_ = x_sensor; }
+  void set_y_sensor(sensor::Sensor *y_sensor) { y_sensor_ = y_sensor; }
+  void set_z_sensor(sensor::Sensor *z_sensor) { z_sensor_ = z_sensor; }
+  void set_heading_sensor(sensor::Sensor *heading_sensor) { heading_sensor_ = heading_sensor; }
+
+ protected:
+  QMC5883LDatarate datarate_{QMC5883L_DATARATE_10_HZ};
+  QMC5883LRange range_{QMC5883L_RANGE_200_UT};
+  QMC5883LOversampling oversampling_{QMC5883L_SAMPLING_512};
+  sensor::Sensor *x_sensor_;
+  sensor::Sensor *y_sensor_;
+  sensor::Sensor *z_sensor_;
+  sensor::Sensor *heading_sensor_;
+  enum ErrorCode {
+    NONE = 0,
+    COMMUNICATION_FAILED,
+  } error_code_;
+  bool read_byte_16_(uint8_t a_register, uint16_t *data);
+};
+
+}  // namespace qmc5883l
+}  // namespace esphome

esphome/components/qmc5883l/sensor.py

@@ -0,0 +1,105 @@
+# coding=utf-8
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.components import i2c, sensor
+from esphome.const import (CONF_ADDRESS, CONF_ID, CONF_OVERSAMPLING, CONF_RANGE, ICON_MAGNET,
+                           UNIT_MICROTESLA, UNIT_DEGREES, ICON_SCREEN_ROTATION,
+                           CONF_UPDATE_INTERVAL)
+from esphome.py_compat import text_type
+
+DEPENDENCIES = ['i2c']
+
+qmc5883l_ns = cg.esphome_ns.namespace('qmc5883l')
+
+CONF_FIELD_STRENGTH_X = 'field_strength_x'
+CONF_FIELD_STRENGTH_Y = 'field_strength_y'
+CONF_FIELD_STRENGTH_Z = 'field_strength_z'
+CONF_HEADING = 'heading'
+
+QMC5883LComponent = qmc5883l_ns.class_(
+    'QMC5883LComponent', cg.PollingComponent, i2c.I2CDevice)
+
+QMC5883LDatarate = qmc5883l_ns.enum('QMC5883LDatarate')
+QMC5883LDatarates = {
+    10: QMC5883LDatarate.QMC5883L_DATARATE_10_HZ,
+    50: QMC5883LDatarate.QMC5883L_DATARATE_50_HZ,
+    100: QMC5883LDatarate.QMC5883L_DATARATE_100_HZ,
+    200: QMC5883LDatarate.QMC5883L_DATARATE_200_HZ,
+}
+
+QMC5883LRange = qmc5883l_ns.enum('QMC5883LRange')
+QMC5883L_RANGES = {
+    200: QMC5883LRange.QMC5883L_RANGE_200_UT,
+    800: QMC5883LRange.QMC5883L_RANGE_800_UT,
+}
+
+QMC5883LOversampling = qmc5883l_ns.enum('QMC5883LOversampling')
+QMC5883LOversamplings = {
+    512: QMC5883LOversampling.QMC5883L_SAMPLING_512,
+    256: QMC5883LOversampling.QMC5883L_SAMPLING_256,
+    128: QMC5883LOversampling.QMC5883L_SAMPLING_128,
+    64: QMC5883LOversampling.QMC5883L_SAMPLING_64,
+}
+
+
+def validate_enum(enum_values, units=None, int=True):
+    _units = []
+    if units is not None:
+        _units = units if isinstance(units, list) else [units]
+        _units = [text_type(x) for x in _units]
+    enum_bound = cv.enum(enum_values, int=int)
+
+    def validate_enum_bound(value):
+        value = cv.string(value)
+        for unit in _units:
+            if value.endswith(unit):
+                value = value[:-len(unit)]
+                break
+        return enum_bound(value)
+    return validate_enum_bound
+
+
+field_strength_schema = sensor.sensor_schema(UNIT_MICROTESLA, ICON_MAGNET, 1)
+heading_schema = sensor.sensor_schema(UNIT_DEGREES, ICON_SCREEN_ROTATION, 1)
+
+CONFIG_SCHEMA = cv.Schema({
+    cv.GenerateID(): cv.declare_id(QMC5883LComponent),
+    cv.Optional(CONF_ADDRESS): cv.i2c_address,
+    cv.Optional(CONF_RANGE, default=u'200µT'): validate_enum(QMC5883L_RANGES, units=["uT", u"µT"]),
+    cv.Optional(CONF_OVERSAMPLING, default="512x"): validate_enum(QMC5883LOversamplings, units="x"),
+    cv.Optional(CONF_FIELD_STRENGTH_X): field_strength_schema,
+    cv.Optional(CONF_FIELD_STRENGTH_Y): field_strength_schema,
+    cv.Optional(CONF_FIELD_STRENGTH_Z): field_strength_schema,
+    cv.Optional(CONF_HEADING): heading_schema,
+}).extend(cv.polling_component_schema('60s')).extend(i2c.i2c_device_schema(0x0D))
+
+
+def auto_data_rate(config):
+    interval_sec = config[CONF_UPDATE_INTERVAL].seconds
+    interval_hz = 1.0/interval_sec
+    for datarate in sorted(QMC5883LDatarates.keys()):
+        if float(datarate) >= interval_hz:
+            return QMC5883LDatarates[datarate]
+    return QMC5883LDatarates[200]
+
+
+def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    yield cg.register_component(var, config)
+    yield i2c.register_i2c_device(var, config)
+
+    cg.add(var.set_oversampling(config[CONF_OVERSAMPLING]))
+    cg.add(var.set_datarate(auto_data_rate(config)))
+    cg.add(var.set_range(config[CONF_RANGE]))
+    if CONF_FIELD_STRENGTH_X in config:
+        sens = yield sensor.new_sensor(config[CONF_FIELD_STRENGTH_X])
+        cg.add(var.set_x_sensor(sens))
+    if CONF_FIELD_STRENGTH_Y in config:
+        sens = yield sensor.new_sensor(config[CONF_FIELD_STRENGTH_Y])
+        cg.add(var.set_y_sensor(sens))
+    if CONF_FIELD_STRENGTH_Z in config:
+        sens = yield sensor.new_sensor(config[CONF_FIELD_STRENGTH_Z])
+        cg.add(var.set_z_sensor(sens))
+    if CONF_HEADING in config:
+        sens = yield sensor.new_sensor(config[CONF_HEADING])
+        cg.add(var.set_heading_sensor(sens))

tests/test1.yaml

@@ -417,6 +417,20 @@ sensor:
     heading:
       name: "HMC5883L Heading"
     range: 130uT
+    oversampling: 8x
+    update_interval: 15s
+  - platform: qmc5883l
+    address: 0x0D
+    field_strength_x:
+      name: "QMC5883L Field Strength X"
+    field_strength_y:
+      name: "QMC5883L Field Strength Y"
+    field_strength_z:
+      name: "QMC5883L Field Strength Z"
+    heading:
+      name: "QMC5883L Heading"
+    range: 800uT
+    oversampling: 256x
     update_interval: 15s
   - platform: hx711
     name: "HX711 Value"