From 882302450956b3070a13cd7bb701dba91b59f132 Mon Sep 17 00:00:00 2001 From: Martin <25747549+martgras@users.noreply.github.com> Date: Thu, 14 Oct 2021 11:24:57 +0200 Subject: [PATCH] Add pressure compensation during runtime (#2493) Co-authored-by: Oxan van Leeuwen --- esphome/components/scd4x/scd4x.cpp | 133 ++++++++++++++++++----------- esphome/components/scd4x/scd4x.h | 9 +- esphome/components/scd4x/sensor.py | 9 +- 3 files changed, 97 insertions(+), 54 deletions(-) diff --git a/esphome/components/scd4x/scd4x.cpp b/esphome/components/scd4x/scd4x.cpp index c91fd5e882..eacb39edf1 100644 --- a/esphome/components/scd4x/scd4x.cpp +++ b/esphome/components/scd4x/scd4x.cpp @@ -1,4 +1,5 @@ #include "scd4x.h" +#include "esphome/core/hal.h" #include "esphome/core/log.h" namespace esphome { @@ -38,6 +39,7 @@ void SCD4XComponent::setup() { return; } + uint32_t stop_measurement_delay = 0; // In order to query the device periodic measurement must be ceased if (raw_read_status[0]) { ESP_LOGD(TAG, "Sensor has data available, stopping periodic measurement"); @@ -46,68 +48,72 @@ void SCD4XComponent::setup() { this->mark_failed(); return; } + // According to the SCD4x datasheet the sensor will only respond to other commands after waiting 500 ms after + // issuing the stop_periodic_measurement command + stop_measurement_delay = 500; } + this->set_timeout(stop_measurement_delay, [this]() { + if (!this->write_command_(SCD4X_CMD_GET_SERIAL_NUMBER)) { + ESP_LOGE(TAG, "Failed to write get serial command"); + this->error_code_ = COMMUNICATION_FAILED; + this->mark_failed(); + return; + } - if (!this->write_command_(SCD4X_CMD_GET_SERIAL_NUMBER)) { - ESP_LOGE(TAG, "Failed to write get serial command"); - this->error_code_ = COMMUNICATION_FAILED; - this->mark_failed(); - return; - } + uint16_t raw_serial_number[3]; + if (!this->read_data_(raw_serial_number, 3)) { + ESP_LOGE(TAG, "Failed to read serial number"); + this->error_code_ = SERIAL_NUMBER_IDENTIFICATION_FAILED; + this->mark_failed(); + return; + } + ESP_LOGD(TAG, "Serial number %02d.%02d.%02d", (uint16_t(raw_serial_number[0]) >> 8), + uint16_t(raw_serial_number[0] & 0xFF), (uint16_t(raw_serial_number[1]) >> 8)); - uint16_t raw_serial_number[3]; - if (!this->read_data_(raw_serial_number, 3)) { - ESP_LOGE(TAG, "Failed to read serial number"); - this->error_code_ = SERIAL_NUMBER_IDENTIFICATION_FAILED; - this->mark_failed(); - return; - } - ESP_LOGD(TAG, "Serial number %02d.%02d.%02d", (uint16_t(raw_serial_number[0]) >> 8), - uint16_t(raw_serial_number[0] & 0xFF), (uint16_t(raw_serial_number[1]) >> 8)); - - if (!this->write_command_(SCD4X_CMD_TEMPERATURE_OFFSET, - (uint16_t)(temperature_offset_ * SCD4X_TEMPERATURE_OFFSET_MULTIPLIER))) { - ESP_LOGE(TAG, "Error setting temperature offset."); - this->error_code_ = MEASUREMENT_INIT_FAILED; - this->mark_failed(); - return; - } - - // If pressure compensation available use it - // else use altitude - if (ambient_pressure_compensation_) { - if (!this->write_command_(SCD4X_CMD_AMBIENT_PRESSURE_COMPENSATION, ambient_pressure_compensation_)) { - ESP_LOGE(TAG, "Error setting ambient pressure compensation."); + if (!this->write_command_(SCD4X_CMD_TEMPERATURE_OFFSET, + (uint16_t)(temperature_offset_ * SCD4X_TEMPERATURE_OFFSET_MULTIPLIER))) { + ESP_LOGE(TAG, "Error setting temperature offset."); this->error_code_ = MEASUREMENT_INIT_FAILED; this->mark_failed(); return; } - } else { - if (!this->write_command_(SCD4X_CMD_ALTITUDE_COMPENSATION, altitude_compensation_)) { - ESP_LOGE(TAG, "Error setting altitude compensation."); + + // If pressure compensation available use it + // else use altitude + if (ambient_pressure_compensation_) { + if (!this->update_ambient_pressure_compensation_(ambient_pressure_)) { + ESP_LOGE(TAG, "Error setting ambient pressure compensation."); + this->error_code_ = MEASUREMENT_INIT_FAILED; + this->mark_failed(); + return; + } + } else { + if (!this->write_command_(SCD4X_CMD_ALTITUDE_COMPENSATION, altitude_compensation_)) { + ESP_LOGE(TAG, "Error setting altitude compensation."); + this->error_code_ = MEASUREMENT_INIT_FAILED; + this->mark_failed(); + return; + } + } + + if (!this->write_command_(SCD4X_CMD_AUTOMATIC_SELF_CALIBRATION, enable_asc_ ? 1 : 0)) { + ESP_LOGE(TAG, "Error setting automatic self calibration."); this->error_code_ = MEASUREMENT_INIT_FAILED; this->mark_failed(); return; } - } - if (!this->write_command_(SCD4X_CMD_AUTOMATIC_SELF_CALIBRATION, enable_asc_ ? 1 : 0)) { - ESP_LOGE(TAG, "Error setting automatic self calibration."); - this->error_code_ = MEASUREMENT_INIT_FAILED; - this->mark_failed(); - return; - } + // Finally start sensor measurements + if (!this->write_command_(SCD4X_CMD_START_CONTINUOUS_MEASUREMENTS)) { + ESP_LOGE(TAG, "Error starting continuous measurements."); + this->error_code_ = MEASUREMENT_INIT_FAILED; + this->mark_failed(); + return; + } - // Finally start sensor measurements - if (!this->write_command_(SCD4X_CMD_START_CONTINUOUS_MEASUREMENTS)) { - ESP_LOGE(TAG, "Error starting continuous measurements."); - this->error_code_ = MEASUREMENT_INIT_FAILED; - this->mark_failed(); - return; - } - - initialized_ = true; - ESP_LOGD(TAG, "Sensor initialized"); + initialized_ = true; + ESP_LOGD(TAG, "Sensor initialized"); + }); }); } @@ -150,6 +156,13 @@ void SCD4XComponent::update() { return; } + if (this->ambient_pressure_source_ != nullptr) { + float pressure = this->ambient_pressure_source_->state / 1000.0f; + if (!std::isnan(pressure)) { + set_ambient_pressure_compensation(this->ambient_pressure_source_->state / 1000.0f); + } + } + // Check if data is ready if (!this->write_command_(SCD4X_CMD_GET_DATA_READY_STATUS)) { this->status_set_warning(); @@ -191,6 +204,28 @@ void SCD4XComponent::update() { this->status_clear_warning(); } +// Note pressure in bar here. Convert to hPa +void SCD4XComponent::set_ambient_pressure_compensation(float pressure_in_bar) { + ambient_pressure_compensation_ = true; + uint16_t new_ambient_pressure = (uint16_t)(pressure_in_bar * 1000); + // remove millibar from comparison to avoid frequent updates +/- 10 millibar doesn't matter + if (initialized_ && (new_ambient_pressure / 10 != ambient_pressure_ / 10)) { + update_ambient_pressure_compensation_(new_ambient_pressure); + ambient_pressure_ = new_ambient_pressure; + } else { + ESP_LOGD(TAG, "ambient pressure compensation skipped - no change required"); + } +} + +bool SCD4XComponent::update_ambient_pressure_compensation_(uint16_t pressure_in_hpa) { + if (this->write_command_(SCD4X_CMD_AMBIENT_PRESSURE_COMPENSATION, pressure_in_hpa)) { + ESP_LOGD(TAG, "setting ambient pressure compensation to %d hPa", pressure_in_hpa); + return true; + } else { + ESP_LOGE(TAG, "Error setting ambient pressure compensation."); + return false; + } +} uint8_t SCD4XComponent::sht_crc_(uint8_t data1, uint8_t data2) { uint8_t bit; diff --git a/esphome/components/scd4x/scd4x.h b/esphome/components/scd4x/scd4x.h index 3c428b8623..4fe2bf14cc 100644 --- a/esphome/components/scd4x/scd4x.h +++ b/esphome/components/scd4x/scd4x.h @@ -18,10 +18,8 @@ class SCD4XComponent : public PollingComponent, public i2c::I2CDevice { void set_automatic_self_calibration(bool asc) { enable_asc_ = asc; } void set_altitude_compensation(uint16_t altitude) { altitude_compensation_ = altitude; } - void set_ambient_pressure_compensation(float pressure) { - ambient_pressure_compensation_ = true; - ambient_pressure_ = (uint16_t)(pressure * 1000); - } + void set_ambient_pressure_compensation(float pressure_in_bar); + void set_ambient_pressure_source(sensor::Sensor *pressure) { ambient_pressure_source_ = pressure; } void set_temperature_offset(float offset) { temperature_offset_ = offset; }; void set_co2_sensor(sensor::Sensor *co2) { co2_sensor_ = co2; } @@ -33,6 +31,7 @@ class SCD4XComponent : public PollingComponent, public i2c::I2CDevice { bool read_data_(uint16_t *data, uint8_t len); bool write_command_(uint16_t command); bool write_command_(uint16_t command, uint16_t data); + bool update_ambient_pressure_compensation_(uint16_t pressure_in_hpa); ERRORCODE error_code_; @@ -47,6 +46,8 @@ class SCD4XComponent : public PollingComponent, public i2c::I2CDevice { sensor::Sensor *co2_sensor_{nullptr}; sensor::Sensor *temperature_sensor_{nullptr}; sensor::Sensor *humidity_sensor_{nullptr}; + // used for compensation + sensor::Sensor *ambient_pressure_source_{nullptr}; }; } // namespace scd4x diff --git a/esphome/components/scd4x/sensor.py b/esphome/components/scd4x/sensor.py index 0b1a960f6f..3e814ffe78 100644 --- a/esphome/components/scd4x/sensor.py +++ b/esphome/components/scd4x/sensor.py @@ -29,6 +29,7 @@ CONF_AUTOMATIC_SELF_CALIBRATION = "automatic_self_calibration" CONF_ALTITUDE_COMPENSATION = "altitude_compensation" CONF_AMBIENT_PRESSURE_COMPENSATION = "ambient_pressure_compensation" CONF_TEMPERATURE_OFFSET = "temperature_offset" +CONF_AMBIENT_PRESSURE_COMPENSATION_SOURCE = "ambient_pressure_compensation_source" CONFIG_SCHEMA = ( cv.Schema( @@ -62,6 +63,9 @@ CONFIG_SCHEMA = ( ), cv.Optional(CONF_AMBIENT_PRESSURE_COMPENSATION): cv.pressure, cv.Optional(CONF_TEMPERATURE_OFFSET, default="4°C"): cv.temperature, + cv.Optional(CONF_AMBIENT_PRESSURE_COMPENSATION_SOURCE): cv.use_id( + sensor.Sensor + ), } ) .extend(cv.polling_component_schema("60s")) @@ -92,7 +96,10 @@ async def to_code(config): cg.add(getattr(var, funcName)(config[key])) for key, funcName in SENSOR_MAP.items(): - if key in config: sens = await sensor.new_sensor(config[key]) cg.add(getattr(var, funcName)(sens)) + + if CONF_AMBIENT_PRESSURE_COMPENSATION_SOURCE in config: + sens = await cg.get_variable(config[CONF_AMBIENT_PRESSURE_COMPENSATION_SOURCE]) + cg.add(var.set_ambient_pressure_source(sens))