Added full support for LTR390UV readings of UV and Lux (#6872)

* Added full support for LTR390UV readings of UV and Lux * Trunk formatting * Added full support for LTR390UV readings of UV and Lux * Trunk formatting * fix library check and unnecessary bit resolution change * fixed log info messages and removed unused dependency * Hopefully fixes git mess * fix variable scope and getMetrics returns * set metrics flags bavk to false in case something wrong happens while reading LTR390UV mode --------- Co-authored-by: Domingo <domingo@waxman.local> Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
2025-12-29 14:10:53 +00:00 · 2025-05-29 16:09:33 +02:00
parent f972b62d89
commit cb9429e83e
4 changed files with 119 additions and 1 deletions
--- a/src/modules/Telemetry/Sensor/LTR390UVSensor.cpp
+++ b/src/modules/Telemetry/Sensor/LTR390UVSensor.cpp
@@ -0,0 +1,73 @@
+#include "configuration.h"
+
+#if !MESHTASTIC_EXCLUDE_ENVIRONMENTAL_SENSOR && __has_include(<Adafruit_LTR390.h>)
+
+#include "../mesh/generated/meshtastic/telemetry.pb.h"
+#include "LTR390UVSensor.h"
+#include "TelemetrySensor.h"
+#include <Adafruit_LTR390.h>
+
+LTR390UVSensor::LTR390UVSensor() : TelemetrySensor(meshtastic_TelemetrySensorType_LTR390UV, "LTR390UV") {}
+
+int32_t LTR390UVSensor::runOnce()
+{
+    LOG_INFO("Init sensor: %s", sensorName);
+    if (!hasSensor()) {
+        return DEFAULT_SENSOR_MINIMUM_WAIT_TIME_BETWEEN_READS;
+    }
+
+    status = ltr390uv.begin(nodeTelemetrySensorsMap[sensorType].second);
+    ltr390uv.setMode(LTR390_MODE_UVS);
+    ltr390uv.setGain(LTR390_GAIN_18);                // Datasheet default
+    ltr390uv.setResolution(LTR390_RESOLUTION_20BIT); // Datasheet default
+
+    return initI2CSensor();
+}
+
+void LTR390UVSensor::setup() {}
+
+bool LTR390UVSensor::getMetrics(meshtastic_Telemetry *measurement)
+{
+    LOG_DEBUG("LTR390UV getMetrics");
+
+    // Because the sensor does not measure Lux and UV at the same time, we need to read them in two passes.
+    if (ltr390uv.newDataAvailable()) {
+        measurement->variant.environment_metrics.has_lux = true;
+        measurement->variant.environment_metrics.has_uv_lux = true;
+
+        if (ltr390uv.getMode() == LTR390_MODE_ALS) {
+            lastLuxReading = 0.6 * ltr390uv.readALS() / (1 * 4); // Datasheet page 23 for gain x1 and 20bit resolution
+            LOG_DEBUG("LTR390UV Lux reading: %f", lastLuxReading);
+
+            measurement->variant.environment_metrics.lux = lastLuxReading;
+            measurement->variant.environment_metrics.uv_lux = lastUVReading;
+
+            ltr390uv.setGain(
+                LTR390_GAIN_18); // Recommended for UVI - x18. Do not change, 2300 UV Sensitivity only specified for x18 gain
+            ltr390uv.setMode(LTR390_MODE_UVS);
+
+            return true;
+
+        } else if (ltr390uv.getMode() == LTR390_MODE_UVS) {
+            lastUVReading = ltr390uv.readUVS() /
+                            2300.f; // Datasheet page 23 and page 6, only characterisation for gain x18 and 20bit resolution
+            LOG_DEBUG("LTR390UV UV reading: %f", lastUVReading);
+
+            measurement->variant.environment_metrics.lux = lastLuxReading;
+            measurement->variant.environment_metrics.uv_lux = lastUVReading;
+
+            ltr390uv.setGain(
+                LTR390_GAIN_1); // x1 gain will already max out the sensor at direct sunlight, so no need to increase it
+            ltr390uv.setMode(LTR390_MODE_ALS);
+
+            return true;
+        }
+    }
+
+    // In case we fail to read the sensor mode, set the has_lux and has_uv_lux back to false
+    measurement->variant.environment_metrics.has_lux = false;
+    measurement->variant.environment_metrics.has_uv_lux = false;
+
+    return false;
+}
+#endif