first fully functional integration (experimental)

src/bme680mems.cpp

@@ -7,60 +7,63 @@ static const char TAG[] = "main";
 
 bmeStatus_t bme_status;
 TaskHandle_t BmeTask;
-float bme_offset = (float)BME_TEMP_OFFSET;
 
 Bsec iaqSensor;
 
+bsec_virtual_sensor_t sensorList[10] = {
+    BSEC_OUTPUT_RAW_TEMPERATURE,
+    BSEC_OUTPUT_RAW_PRESSURE,
+    BSEC_OUTPUT_RAW_HUMIDITY,
+    BSEC_OUTPUT_RAW_GAS,
+    BSEC_OUTPUT_IAQ,
+    BSEC_OUTPUT_STATIC_IAQ,
+    BSEC_OUTPUT_CO2_EQUIVALENT,
+    BSEC_OUTPUT_BREATH_VOC_EQUIVALENT,
+    BSEC_OUTPUT_SENSOR_HEAT_COMPENSATED_TEMPERATURE,
+    BSEC_OUTPUT_SENSOR_HEAT_COMPENSATED_HUMIDITY,
+};
+
 // initialize BME680 sensor
 int bme_init(void) {
 
-  Wire.begin(HAS_BME);
-  iaqSensor.begin(BME_ADDR, Wire);
+  // block i2c bus access
+  if (xSemaphoreTake(I2Caccess, (DISPLAYREFRESH_MS / portTICK_PERIOD_MS)) ==
+      pdTRUE) {
 
-  ESP_LOGI(TAG, "BSEC v%d.%d.%d.%d", iaqSensor.version.major,
-           iaqSensor.version.minor, iaqSensor.version.major_bugfix,
-           iaqSensor.version.minor_bugfix);
+    Wire.begin(HAS_BME);
+    iaqSensor.begin(BME_ADDR, Wire);
 
-  iaqSensor.setConfig(bsec_config_iaq);
+    ESP_LOGI(TAG, "BSEC v%d.%d.%d.%d", iaqSensor.version.major,
+             iaqSensor.version.minor, iaqSensor.version.major_bugfix,
+             iaqSensor.version.minor_bugfix);
 
-  if (checkIaqSensorStatus())
-    ESP_LOGI(TAG, "BME680 sensor found and initialized");
-  else {
-    ESP_LOGE(TAG, "BME680 sensor not found");
+    iaqSensor.setConfig(bsec_config_iaq);
+
+    if (checkIaqSensorStatus())
+      ESP_LOGI(TAG, "BME680 sensor found and initialized");
+    else {
+      ESP_LOGE(TAG, "BME680 sensor not found");
+      return 1;
+    }
+
+    iaqSensor.setTemperatureOffset((float)BME_TEMP_OFFSET);
+    iaqSensor.updateSubscription(sensorList, 10, BSEC_SAMPLE_RATE_LP);
+
+    if (checkIaqSensorStatus())
+      ESP_LOGI(TAG, "BSEC subscription succesful");
+    else {
+      ESP_LOGE(TAG, "BSEC subscription error");
+      return 1;
+    }
+
+    xSemaphoreGive(I2Caccess); // release i2c bus access
+
+  } else {
+    ESP_LOGE(TAG, "I2c bus busy - BME680 initialization error");
     return 1;
   }
 
-  bsec_virtual_sensor_t sensorList[10] = {
-      BSEC_OUTPUT_RAW_TEMPERATURE,
-      BSEC_OUTPUT_RAW_PRESSURE,
-      BSEC_OUTPUT_RAW_HUMIDITY,
-      BSEC_OUTPUT_RAW_GAS,
-      BSEC_OUTPUT_IAQ,
-      BSEC_OUTPUT_STATIC_IAQ,
-      BSEC_OUTPUT_CO2_EQUIVALENT,
-      BSEC_OUTPUT_BREATH_VOC_EQUIVALENT,
-      BSEC_OUTPUT_SENSOR_HEAT_COMPENSATED_TEMPERATURE,
-      BSEC_OUTPUT_SENSOR_HEAT_COMPENSATED_HUMIDITY,
-  };
-
-  iaqSensor.updateSubscription(sensorList, 10, BSEC_SAMPLE_RATE_LP);
-
-  if (checkIaqSensorStatus())
-    ESP_LOGI(TAG, "BSEC subscription succesful");
-  else {
-    ESP_LOGE(TAG, "BSEC subscription error");
-    return 1;
-  }
-
-  iaqSensor.setTemperatureOffset(bme_offset);
-
-  if (checkIaqSensorStatus())
-    ESP_LOGI(TAG, "Ttemperature offset initialized succesful");
-  else {
-    ESP_LOGE(TAG, "Temperature offset initialization error");
-    return 1;
-  }
-}
+} // bme_init()
 
 // Helper function definitions
 int checkIaqSensorStatus(void) {
@@ -83,7 +86,7 @@ int checkIaqSensorStatus(void) {
   }
 
   return rslt;
-}
+} // checkIaqSensorStatus()
 
 // loop function which reads and processes data based on sensor settings
 void bme_loop(void *pvParameters) {
@@ -92,16 +95,24 @@ void bme_loop(void *pvParameters) {
 
 #ifdef HAS_BME
   while (checkIaqSensorStatus()) {
-    if (iaqSensor.run()) { // If new data is available
-      bme_status.raw_temperature = iaqSensor.rawTemperature;
-      bme_status.raw_humidity = iaqSensor.rawHumidity;
-      bme_status.temperature = iaqSensor.temperature;
-      bme_status.humidity = iaqSensor.humidity;
-      bme_status.pressure =
-          (iaqSensor.pressure / 100.0); // conversion Pa -> hPa
-      bme_status.iaq = iaqSensor.iaqEstimate;
-      bme_status.iaq_accuracy = iaqSensor.iaqAccuracy;
-      bme_status.gas = iaqSensor.gasResistance;
+
+    // block i2c bus access
+    if (xSemaphoreTake(I2Caccess, (DISPLAYREFRESH_MS / portTICK_PERIOD_MS)) ==
+        pdTRUE) {
+
+      if (iaqSensor.run()) { // If new data is available
+        bme_status.raw_temperature = iaqSensor.rawTemperature;
+        bme_status.raw_humidity = iaqSensor.rawHumidity;
+        bme_status.temperature = iaqSensor.temperature;
+        bme_status.humidity = iaqSensor.humidity;
+        bme_status.pressure =
+            (iaqSensor.pressure / 100.0); // conversion Pa -> hPa
+        bme_status.iaq = iaqSensor.iaqEstimate;
+        bme_status.iaq_accuracy = iaqSensor.iaqAccuracy;
+        bme_status.gas = iaqSensor.gasResistance;
+      }
+
+      xSemaphoreGive(I2Caccess); // release i2c bus access
     }
   }
 #endif

src/cyclic.cpp

@@ -52,7 +52,12 @@ void doHousekeeping() {
 // read battery voltage into global variable
 #ifdef HAS_BATTERY_PROBE
   batt_voltage = read_voltage();
-  ESP_LOGI(TAG, "Measured Voltage: %dmV", batt_voltage);
+  ESP_LOGI(TAG, "Voltage: %dmV", batt_voltage);
+#endif
+
+// display BME sensor data if present
+#ifdef HAS_BME
+  ESP_LOGI(TAG, "BME680 Temp: %.2f°C | IAQ: %.2f", bme_status.temperature, bme_status.iaq);
 #endif
 
   // check free heap memory

src/display.cpp

@@ -98,96 +98,104 @@ void init_display(const char *Productname, const char *Version) {
 
 void refreshtheDisplay() {
 
-  // set display on/off according to current device configuration
-  if (DisplayState != cfg.screenon) {
-    DisplayState = cfg.screenon;
-    u8x8.setPowerSave(!cfg.screenon);
-  }
+  // block i2c bus access
+  if (xSemaphoreTake(I2Caccess, (DISPLAYREFRESH_MS / portTICK_PERIOD_MS)) ==
+      pdTRUE) {
 
-  // if display is switched off we don't refresh it and save time
-  if (!DisplayState)
-    return;
+    // set display on/off according to current device configuration
+    if (DisplayState != cfg.screenon) {
+      DisplayState = cfg.screenon;
+      u8x8.setPowerSave(!cfg.screenon);
+    }
 
-  uint8_t msgWaiting;
-  char buff[16]; // 16 chars line buffer
+    // if display is switched off we don't refresh it and save time
+    if (!DisplayState)
+      return;
 
-  // update counter (lines 0-1)
-  snprintf(
-      buff, sizeof(buff), "PAX:%-4d",
-      (int)macs.size()); // convert 16-bit MAC counter to decimal counter value
-  u8x8.draw2x2String(0, 0,
-                     buff); // display number on unique macs total Wifi + BLE
+    uint8_t msgWaiting;
+    char buff[16]; // 16 chars line buffer
+
+    // update counter (lines 0-1)
+    snprintf(
+        buff, sizeof(buff), "PAX:%-4d",
+        (int)
+            macs.size()); // convert 16-bit MAC counter to decimal counter value
+    u8x8.draw2x2String(0, 0,
+                       buff); // display number on unique macs total Wifi + BLE
 
 // update Battery status (line 2)
 #ifdef HAS_BATTERY_PROBE
-  u8x8.setCursor(0, 2);
-  u8x8.printf("B:%.1fV", batt_voltage / 1000.0);
+    u8x8.setCursor(0, 2);
+    u8x8.printf("B:%.1fV", batt_voltage / 1000.0);
 #endif
 
 // update GPS status (line 2)
 #ifdef HAS_GPS
-  u8x8.setCursor(9, 2);
-  if (!gps.location.isValid()) // if no fix then display Sats value inverse
-  {
-    u8x8.setInverseFont(1);
-    u8x8.printf("Sats:%.2d", gps.satellites.value());
-    u8x8.setInverseFont(0);
-  } else
-    u8x8.printf("Sats:%.2d", gps.satellites.value());
+    u8x8.setCursor(9, 2);
+    if (!gps.location.isValid()) // if no fix then display Sats value inverse
+    {
+      u8x8.setInverseFont(1);
+      u8x8.printf("Sats:%.2d", gps.satellites.value());
+      u8x8.setInverseFont(0);
+    } else
+      u8x8.printf("Sats:%.2d", gps.satellites.value());
 #endif
 
-    // update bluetooth counter + LoRa SF (line 3)
+      // update bluetooth counter + LoRa SF (line 3)
 #ifdef BLECOUNTER
-  u8x8.setCursor(0, 3);
-  if (cfg.blescan)
-    u8x8.printf("BLTH:%-4d", macs_ble);
-  else
-    u8x8.printf("%s", "BLTH:off");
+    u8x8.setCursor(0, 3);
+    if (cfg.blescan)
+      u8x8.printf("BLTH:%-4d", macs_ble);
+    else
+      u8x8.printf("%s", "BLTH:off");
 #endif
 
 #ifdef HAS_LORA
-  u8x8.setCursor(11, 3);
-  u8x8.printf("SF:");
-  if (cfg.adrmode) // if ADR=on then display SF value inverse
-    u8x8.setInverseFont(1);
-  u8x8.printf("%c%c", lora_datarate[LMIC.datarate * 2],
-              lora_datarate[LMIC.datarate * 2 + 1]);
-  if (cfg.adrmode) // switch off inverse if it was turned on
-    u8x8.setInverseFont(0);
+    u8x8.setCursor(11, 3);
+    u8x8.printf("SF:");
+    if (cfg.adrmode) // if ADR=on then display SF value inverse
+      u8x8.setInverseFont(1);
+    u8x8.printf("%c%c", lora_datarate[LMIC.datarate * 2],
+                lora_datarate[LMIC.datarate * 2 + 1]);
+    if (cfg.adrmode) // switch off inverse if it was turned on
+      u8x8.setInverseFont(0);
 #endif // HAS_LORA
 
-  // update wifi counter + channel display (line 4)
-  u8x8.setCursor(0, 4);
-  u8x8.printf("WIFI:%-4d", macs_wifi);
-  u8x8.setCursor(11, 4);
-  u8x8.printf("ch:%02d", channel);
+    // update wifi counter + channel display (line 4)
+    u8x8.setCursor(0, 4);
+    u8x8.printf("WIFI:%-4d", macs_wifi);
+    u8x8.setCursor(11, 4);
+    u8x8.printf("ch:%02d", channel);
 
-  // update RSSI limiter status & free memory display (line 5)
-  u8x8.setCursor(0, 5);
-  u8x8.printf(!cfg.rssilimit ? "RLIM:off " : "RLIM:%-4d", cfg.rssilimit);
-  u8x8.setCursor(10, 5);
-  u8x8.printf("%4dKB", getFreeRAM() / 1024);
+    // update RSSI limiter status & free memory display (line 5)
+    u8x8.setCursor(0, 5);
+    u8x8.printf(!cfg.rssilimit ? "RLIM:off " : "RLIM:%-4d", cfg.rssilimit);
+    u8x8.setCursor(10, 5);
+    u8x8.printf("%4dKB", getFreeRAM() / 1024);
 
 #ifdef HAS_LORA
-  // update LoRa status display (line 6)
-  u8x8.setCursor(0, 6);
-  u8x8.printf("%-16s", display_line6);
+    // update LoRa status display (line 6)
+    u8x8.setCursor(0, 6);
+    u8x8.printf("%-16s", display_line6);
 
-  // update LMiC event display (line 7)
-  u8x8.setCursor(0, 7);
-  u8x8.printf("%-14s", display_line7);
+    // update LMiC event display (line 7)
+    u8x8.setCursor(0, 7);
+    u8x8.printf("%-14s", display_line7);
 
-  // update LoRa send queue display (line 7)
-  msgWaiting = uxQueueMessagesWaiting(LoraSendQueue);
-  if (msgWaiting) {
-    sprintf(buff, "%2d", msgWaiting);
-    u8x8.setCursor(14, 7);
-    u8x8.printf("%-2s", msgWaiting == SEND_QUEUE_SIZE ? "<>" : buff);
-  } else
-    u8x8.printf("  ");
+    // update LoRa send queue display (line 7)
+    msgWaiting = uxQueueMessagesWaiting(LoraSendQueue);
+    if (msgWaiting) {
+      sprintf(buff, "%2d", msgWaiting);
+      u8x8.setCursor(14, 7);
+      u8x8.printf("%-2s", msgWaiting == SEND_QUEUE_SIZE ? "<>" : buff);
+    } else
+      u8x8.printf("  ");
 
 #endif // HAS_LORA
 
+    xSemaphoreGive(I2Caccess); // release i2c bus access
+  }
+
 } // refreshDisplay()
 
 #endif // HAS_DISPLAY

src/hal/ttgobeam_new.h

@@ -19,10 +19,10 @@
 // user defined sensors
 //#define HAS_SENSORS 1 // comment out if device has user defined sensors
 
-//#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
-//#define MY_OLED_SDA (21)
-//#define MY_OLED_SCL (22)
-//#define MY_OLED_RST (NOT_A_PIN)
+#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
+#define MY_OLED_SDA (21)
+#define MY_OLED_SCL (22)
+#define MY_OLED_RST U8X8_PIN_NONE
 //#define DISPLAY_FLIP  1 // use if display is rotated
 
 #define HAS_LORA 1       // comment out if device shall not send data via LoRa

src/hal/ttgobeam_old.h

@@ -22,7 +22,7 @@
 //#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
 //#define MY_OLED_SDA (21)
 //#define MY_OLED_SCL (22)
-//#define MY_OLED_RST (NOT_A_PIN)
+//#define MY_OLED_RST U8X8_PIN_NONE
 //#define DISPLAY_FLIP  1 // use if display is rotated
 
 #define HAS_LORA 1       // comment out if device shall not send data via LoRa

src/main.cpp

@@ -35,11 +35,14 @@ IDLE          0     0     ESP32 arduino scheduler -> runs wifi sniffer
 looptask      1     1     arduino core -> runs the LMIC LoRa stack
 irqhandler    1     1     executes tasks triggered by irq
 gpsloop       1     2     reads data from GPS via serial or i2c
-bmeloop       1     0     reads data from BME sensor via i2c
+bmeloop       1     1     reads data from BME sensor via i2c
 IDLE          1     0     ESP32 arduino scheduler
 
 Low priority numbers denote low priority tasks.
 
+Tasks using i2c bus all must have same priority, because using mutex semaphore
+(irqhandler, bmeloop)
+
 ESP32 hardware timers
 ==========================
  0	Trigger display refresh
@@ -60,6 +63,7 @@ uint16_t volatile macs_total = 0, macs_wifi = 0, macs_ble = 0,
 hw_timer_t *channelSwitch = NULL, *sendCycle = NULL, *homeCycle = NULL,
            *displaytimer = NULL; // irq tasks
 TaskHandle_t irqHandlerTask, wifiSwitchTask;
+SemaphoreHandle_t I2Caccess;
 
 // container holding unique MAC address hashes with Memory Alloctor using PSRAM,
 // if present
@@ -78,6 +82,14 @@ void setup() {
 
   char features[100] = "";
 
+  if (I2Caccess == NULL) // Check that semaphore has not already been created
+  {
+    I2Caccess = xSemaphoreCreateMutex(); // Create a mutex semaphore we will use
+                                         // to manage the i2c bus
+    if ((I2Caccess) != NULL)
+      xSemaphoreGive((I2Caccess)); // Flag the i2c bus available for use
+  }
+
   // disable brownout detection
 #ifdef DISABLE_BROWNOUT
   // register with brownout is at address DR_REG_RTCCNTL_BASE + 0xd4
@@ -343,11 +355,11 @@ void setup() {
                             "bmeloop", // name of task
                             4096,      // stack size of task
                             (void *)1, // parameter of the task
-                            0,         // priority of the task
+                            //0,         // priority of the task
+                            1,         // priority of the task
                             &BmeTask,  // task handle
                             1);        // CPU core
   }
-  delay(2000); // time for initializing i2c sensor
 #endif
 
   // start timer triggered interrupts