From cae27c1764afeb66e4313bc844a225f83c44af71 Mon Sep 17 00:00:00 2001
From: oscgonfer <oscgonfer@users.noreply.github.com>
Date: Sat, 18 Jul 2026 20:52:39 +0200
Subject: [PATCH] Add retries for SCD4X data reading (#11058)

* Add retries for SCD4X data reading

* Adds a retry loop with 3 tries by default to get sensor data from the SCD4X

* Fix log and happy path
---
 src/modules/Telemetry/Sensor/SCD4XSensor.cpp | 14 ++++++++++++--
 src/modules/Telemetry/Sensor/SCD4XSensor.h   |  1 +
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/modules/Telemetry/Sensor/SCD4XSensor.cpp b/src/modules/Telemetry/Sensor/SCD4XSensor.cpp
index bae0cf12a..26d50ab3e 100644
--- a/src/modules/Telemetry/Sensor/SCD4XSensor.cpp
+++ b/src/modules/Telemetry/Sensor/SCD4XSensor.cpp
@@ -104,8 +104,18 @@ bool SCD4XSensor::getMetrics(meshtastic_Telemetry *measurement)
     reClockI2C.setClock(SCD4X_I2C_CLOCK_SPEED);
 #endif /* SCD4X_I2C_CLOCK_SPEED */
 
-    bool dataReady;
-    error = scd4x.getDataReadyStatus(dataReady);
+    bool dataReady = false;
+    uint8_t dataReadyTries = 0;
+
+    while (!dataReady && (dataReadyTries < SCD4X_MAX_RETRIES)) {
+        error = scd4x.getDataReadyStatus(dataReady);
+        if (error != SCD4X_NO_ERROR || !dataReady) {
+            LOG_WARN("%s: Error collecting data. Retrying", sensorName);
+            delay(100);
+            dataReadyTries++;
+        }
+    }
+
     if (error != SCD4X_NO_ERROR || !dataReady) {
 #ifdef SCD4X_I2C_CLOCK_SPEED
         LOG_DEBUG("%s: restoring clock speed", sensorName);
diff --git a/src/modules/Telemetry/Sensor/SCD4XSensor.h b/src/modules/Telemetry/Sensor/SCD4XSensor.h
index 065c82a13..f9161942e 100644
--- a/src/modules/Telemetry/Sensor/SCD4XSensor.h
+++ b/src/modules/Telemetry/Sensor/SCD4XSensor.h
@@ -11,6 +11,7 @@
 // Max speed 400kHz
 #define SCD4X_I2C_CLOCK_SPEED 400000
 #define SCD4X_WARMUP_MS 5000
+#define SCD4X_MAX_RETRIES 3
 
 class SCD4XSensor : public TelemetrySensor
 {