use serial number to determine hash

esphome · Oct 25, 2023 · 8585e93 · 8585e93
1 parent e80bd8e
commit 8585e93
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Showing 3 changed files with 11 additions and 6 deletions.
diff --git a/esphome/components/sen5x/sen5x.cpp b/esphome/components/sen5x/sen5x.cpp
@@ -135,9 +135,12 @@ void SEN5XComponent::setup() {
       ESP_LOGD(TAG, "Firmware version %d", this->firmware_version_);
 
       if (this->voc_sensor_ && this->store_baseline_) {
-        // Hash with compilation time
+        uint32_t combined_serial = (uint32_t(this->serial_number_[0]) << 24) |
+                                   (uint32_t(this->serial_number_[1]) << 16) | (uint32_t(this->serial_number_[2]));
+        // Hash with compilation time and serial number
         // This ensures the baseline storage is cleared after OTA
-        uint32_t hash = fnv1_hash(App.get_compilation_time());
+        // Serial numbers are unique to each sensor, so mulitple sensors can be used without conflict
+        uint32_t hash = fnv1_hash(App.get_compilation_time() + std::to_string(combined_serial));
         this->pref_ = global_preferences->make_preference<Sen5xBaselines>(hash, true);
 
         if (this->pref_.load(&this->voc_baselines_storage_)) {

diff --git a/esphome/components/sgp30/sgp30.cpp b/esphome/components/sgp30/sgp30.cpp
@@ -73,9 +73,10 @@ void SGP30Component::setup() {
     return;
   }
 
-  // Hash with compilation time
+  // Hash with compilation time and serial number
   // This ensures the baseline storage is cleared after OTA
-  uint32_t hash = fnv1_hash(App.get_compilation_time());
+  // Serial numbers are unique to each sensor, so mulitple sensors can be used without conflict
+  uint32_t hash = fnv1_hash(App.get_compilation_time() + std::to_string(this->serial_number_));
   this->pref_ = global_preferences->make_preference<SGP30Baselines>(hash, true);
 
   if (this->pref_.load(&this->baselines_storage_)) {

diff --git a/esphome/components/sgp4x/sgp4x.cpp b/esphome/components/sgp4x/sgp4x.cpp
@@ -61,9 +61,10 @@ void SGP4xComponent::setup() {
   ESP_LOGD(TAG, "Product version: 0x%0X", uint16_t(this->featureset_ & 0x1FF));
 
   if (this->store_baseline_) {
-    // Hash with compilation time
+    // Hash with compilation time and serial number
     // This ensures the baseline storage is cleared after OTA
-    uint32_t hash = fnv1_hash(App.get_compilation_time());
+    // Serial numbers are unique to each sensor, so mulitple sensors can be used without conflict
+    uint32_t hash = fnv1_hash(App.get_compilation_time() + std::to_string(this->serial_number_));
     this->pref_ = global_preferences->make_preference<SGP4xBaselines>(hash, true);
 
     if (this->pref_.load(&this->voc_baselines_storage_)) {