TSL2591 automatic gain control (#3071)

This commit is contained in:
Nicholas Peters 2022-01-26 04:48:51 -05:00 committed by GitHub
parent 511c8de6f3
commit c5974b8833
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GPG key ID: 4AEE18F83AFDEB23
3 changed files with 101 additions and 19 deletions

View file

@ -56,18 +56,19 @@ INTEGRATION_TIMES = {
600: TSL2591IntegrationTime.TSL2591_INTEGRATION_TIME_600MS,
}
TSL2591Gain = tsl2591_ns.enum("TSL2591Gain")
TSL2591ComponentGain = tsl2591_ns.enum("TSL2591ComponentGain")
GAINS = {
"1X": TSL2591Gain.TSL2591_GAIN_LOW,
"LOW": TSL2591Gain.TSL2591_GAIN_LOW,
"25X": TSL2591Gain.TSL2591_GAIN_MED,
"MED": TSL2591Gain.TSL2591_GAIN_MED,
"MEDIUM": TSL2591Gain.TSL2591_GAIN_MED,
"400X": TSL2591Gain.TSL2591_GAIN_HIGH,
"HIGH": TSL2591Gain.TSL2591_GAIN_HIGH,
"9500X": TSL2591Gain.TSL2591_GAIN_MAX,
"MAX": TSL2591Gain.TSL2591_GAIN_MAX,
"MAXIMUM": TSL2591Gain.TSL2591_GAIN_MAX,
"1X": TSL2591ComponentGain.TSL2591_CGAIN_LOW,
"LOW": TSL2591ComponentGain.TSL2591_CGAIN_LOW,
"25X": TSL2591ComponentGain.TSL2591_CGAIN_MED,
"MED": TSL2591ComponentGain.TSL2591_CGAIN_MED,
"MEDIUM": TSL2591ComponentGain.TSL2591_CGAIN_MED,
"400X": TSL2591ComponentGain.TSL2591_CGAIN_HIGH,
"HIGH": TSL2591ComponentGain.TSL2591_CGAIN_HIGH,
"9500X": TSL2591ComponentGain.TSL2591_CGAIN_MAX,
"MAX": TSL2591ComponentGain.TSL2591_CGAIN_MAX,
"MAXIMUM": TSL2591ComponentGain.TSL2591_CGAIN_MAX,
"AUTO": TSL2591ComponentGain.TSL2591_CGAIN_AUTO,
}
@ -117,7 +118,7 @@ CONFIG_SCHEMA = (
CONF_INTEGRATION_TIME, default="100ms"
): validate_integration_time,
cv.Optional(CONF_NAME, default="TLS2591"): cv.string,
cv.Optional(CONF_GAIN, default="MEDIUM"): cv.enum(GAINS, upper=True),
cv.Optional(CONF_GAIN, default="AUTO"): cv.enum(GAINS, upper=True),
cv.Optional(CONF_POWER_SAVE_MODE, default=True): cv.boolean,
cv.Optional(CONF_DEVICE_FACTOR, default=53.0): cv.float_with_unit(
"device_factor", "", True

View file

@ -43,6 +43,8 @@ void TSL2591Component::disable_if_power_saving_() {
}
void TSL2591Component::setup() {
if (this->component_gain_ == TSL2591_CGAIN_AUTO)
this->gain_ = TSL2591_GAIN_MED;
uint8_t address = this->address_;
ESP_LOGI(TAG, "Setting up TSL2591 sensor at I2C address 0x%02X", address);
uint8_t id;
@ -73,26 +75,30 @@ void TSL2591Component::dump_config() {
}
ESP_LOGCONFIG(TAG, " Name: %s", this->name_);
TSL2591Gain raw_gain = this->gain_;
TSL2591ComponentGain raw_gain = this->component_gain_;
int gain = 0;
std::string gain_word = "unknown";
switch (raw_gain) {
case TSL2591_GAIN_LOW:
case TSL2591_CGAIN_LOW:
gain = 1;
gain_word = "low";
break;
case TSL2591_GAIN_MED:
case TSL2591_CGAIN_MED:
gain = 25;
gain_word = "medium";
break;
case TSL2591_GAIN_HIGH:
case TSL2591_CGAIN_HIGH:
gain = 400;
gain_word = "high";
break;
case TSL2591_GAIN_MAX:
case TSL2591_CGAIN_MAX:
gain = 9500;
gain_word = "maximum";
break;
case TSL2591_CGAIN_AUTO:
gain = -1;
gain_word = "auto";
break;
}
ESP_LOGCONFIG(TAG, " Gain: %dx (%s)", gain, gain_word.c_str());
TSL2591IntegrationTime raw_timing = this->integration_time_;
@ -129,6 +135,9 @@ void TSL2591Component::process_update_() {
if (this->calculated_lux_sensor_ != nullptr) {
this->calculated_lux_sensor_->publish_state(lux);
}
if (this->component_gain_ == TSL2591_CGAIN_AUTO) {
this->automatic_gain_update(full);
}
this->status_clear_warning();
}
@ -183,7 +192,7 @@ void TSL2591Component::set_integration_time(TSL2591IntegrationTime integration_t
this->integration_time_ = integration_time;
}
void TSL2591Component::set_gain(TSL2591Gain gain) { this->gain_ = gain; }
void TSL2591Component::set_gain(TSL2591ComponentGain gain) { this->component_gain_ = gain; }
void TSL2591Component::set_device_and_glass_attenuation_factors(float device_factor, float glass_attenuation_factor) {
this->device_factor_ = device_factor;
@ -366,5 +375,56 @@ float TSL2591Component::get_calculated_lux(uint16_t full_spectrum, uint16_t infr
return std::max(lux, 0.0F);
}
/** Calculates and updates the sensor gain setting, trying to keep the full spectrum counts near
* the middle of the range
*
* It's hard to tell how far down to turn the gain when it's at the top of the scale, so decrease
* the gain by up to 2 steps if it's near the top to be sure we get a good reading next time.
* Increase gain by max 2 steps per reading.
*
* If integration time is 100 MS, divide the upper thresholds by 2 to account for ADC saturation
*
* @param full_spectrum The ADC reading for TSL2591 channel 0.
*
* 1/3 FS = 21,845
*/
void TSL2591Component::automatic_gain_update(uint16_t full_spectrum) {
TSL2591Gain new_gain = this->gain_;
uint fs_divider = (this->integration_time_ == TSL2591_INTEGRATION_TIME_100MS) ? 2 : 1;
switch (this->gain_) {
case TSL2591_GAIN_LOW:
if (full_spectrum < 54) // 1/3 FS / GAIN_HIGH
new_gain = TSL2591_GAIN_HIGH;
else if (full_spectrum < 875) // 1/3 FS / GAIN_MED
new_gain = TSL2591_GAIN_MED;
break;
case TSL2591_GAIN_MED:
if (full_spectrum < 57) // 1/3 FS / (GAIN_MAX/GAIN_MED)
new_gain = TSL2591_GAIN_MAX;
else if (full_spectrum < 1365) // 1/3 FS / (GAIN_HIGH/GAIN_MED)
new_gain = TSL2591_GAIN_HIGH;
else if (full_spectrum > 62000 / fs_divider) // 2/3 FS / (GAIN_LOW/GAIN_MED) clipped to 95% FS
new_gain = TSL2591_GAIN_LOW;
break;
case TSL2591_GAIN_HIGH:
if (full_spectrum < 920) // 1/3 FS / (GAIN_MAX/GAIN_HIGH)
new_gain = TSL2591_GAIN_MAX;
else if (full_spectrum > 62000 / fs_divider) // 2/3 FS / (GAIN_MED/GAIN_HIGH) clipped to 95% FS
new_gain = TSL2591_GAIN_LOW;
break;
case TSL2591_GAIN_MAX:
if (full_spectrum > 62000 / fs_divider) // 2/3 FS / (GAIN_MED/GAIN_HIGH) clipped to 95% FS
new_gain = TSL2591_GAIN_MED;
break;
}
if (this->gain_ != new_gain) {
this->gain_ = new_gain;
this->set_integration_time_and_gain(this->integration_time_, this->gain_);
}
ESP_LOGD(TAG, "Gain setting: %d", this->gain_);
}
} // namespace tsl2591
} // namespace esphome

View file

@ -21,6 +21,19 @@ enum TSL2591IntegrationTime {
TSL2591_INTEGRATION_TIME_600MS = 0b101,
};
/** Enum listing all gain settings for the TSL2591 component.
*
* Enum constants are used by the component to allow auto gain, not directly to registers
* Higher values are better for low light situations, but can increase noise.
*/
enum TSL2591ComponentGain {
TSL2591_CGAIN_LOW, // 1x
TSL2591_CGAIN_MED, // 25x
TSL2591_CGAIN_HIGH, // 400x
TSL2591_CGAIN_MAX, // 9500x
TSL2591_CGAIN_AUTO
};
/** Enum listing all gain settings for the TSL2591.
*
* Specific values of the enum constants are register values taken from the TSL2591 datasheet.
@ -200,6 +213,13 @@ class TSL2591Component : public PollingComponent, public i2c::I2CDevice {
*/
void disable();
/** Updates the gain setting based on the most recent full spectrum reading
*
* This gets called on update and tries to keep the ADC readings in the middle of the range
*/
void automatic_gain_update(uint16_t full_spectrum);
// ========== INTERNAL METHODS ==========
// (In most use cases you won't need these. They're for ESPHome integration use.)
/** Used by ESPHome framework. */
@ -213,7 +233,7 @@ class TSL2591Component : public PollingComponent, public i2c::I2CDevice {
/** Used by ESPHome framework. Does NOT actually set the value on the device. */
void set_integration_time(TSL2591IntegrationTime integration_time);
/** Used by ESPHome framework. Does NOT actually set the value on the device. */
void set_gain(TSL2591Gain gain);
void set_gain(TSL2591ComponentGain gain);
/** Used by ESPHome framework. */
void setup() override;
/** Used by ESPHome framework. */
@ -230,6 +250,7 @@ class TSL2591Component : public PollingComponent, public i2c::I2CDevice {
sensor::Sensor *visible_sensor_;
sensor::Sensor *calculated_lux_sensor_;
TSL2591IntegrationTime integration_time_;
TSL2591ComponentGain component_gain_;
TSL2591Gain gain_;
bool power_save_mode_enabled_;
float device_factor_;