add bsec persistence

main/co2_sensor.c

@@ -13,6 +13,8 @@
 #include "settings.h"
 #include <driver/uart.h>
 #include <string.h>
+#include <stddef.h>
+#include <inttypes.h>
 
 static const char *TAG = "co2";
 
@@ -77,7 +79,7 @@ static bool ppm_looks_valid(uint16_t ppm) {
 }
 
 void co2_read_task(void *param) {
-    esp_err_t rv;
+    (void) param;
 
     vTaskDelay(pdMS_TO_TICKS(500));
 
@@ -91,8 +93,10 @@ void co2_read_task(void *param) {
 
     write_saved_calib_to_sensor();
 
-    const uint32_t read_cycle_time_ticks = pdMS_TO_TICKS(10 * 1000);
-    const uint32_t calib_persist_time_ticks = pdMS_TO_TICKS(6 * 3600 * 1000);
+    const uint32_t read_cycle_time_ticks = 10 * 1000;
+    const uint32_t calib_persist_time_ticks = 12 * 3600 * 1000;
+    _Static_assert(configTICK_RATE_HZ == 1000, "1kHz tick");
+
     uint32_t last_calib_persist = xTaskGetTickCount();
 
     ESP_LOGD(TAG, "Calib persist time = %d ticks", calib_persist_time_ticks);
@@ -176,7 +180,8 @@ void co2_read_task(void *param) {
             // CO2 measurement looks OK
 
             uint32_t tickNow = xTaskGetTickCount();
-            if ((tickNow - last_calib_persist) > calib_persist_time_ticks) {
+            uint32_t elapsed = tickNow - last_calib_persist;
+            if (elapsed > calib_persist_time_ticks) {
                 ESP_LOGI(TAG, "Read & persist CO2 calibration");
 
                 last_calib_persist = tickNow;

main/settings.c

@@ -122,12 +122,16 @@ void settings_load(void)
         size_t capacity = 10;
         NVSCHECK(nvs_get_blob(storage, "co2_calib", g_Settings.co2_calib, &capacity));
     }
+    {
+        size_t capacity = BSEC_MAX_STATE_BLOB_SIZE;
+        NVSCHECK(nvs_get_blob(storage, "bsec_state", g_Settings.bsec_state, &capacity));
+    }
 }
 
 void settings_persist(enum settings_key_enum what)
 {
     esp_err_t rv;
-    char name[24];
+//    char name[24];
 
     #undef NVSCHECK
     #define NVSCHECK(callback) \
@@ -160,6 +164,10 @@ void settings_persist(enum settings_key_enum what)
     if (what==SETTINGS_ALL || what==SETTINGS_co2_calib) {
         NVSCHECK(nvs_set_blob(storage, "co2_calib", (void*) g_Settings.co2_calib, 5*sizeof(uint16_t)));
     }
+
+    if (what==SETTINGS_ALL || what==SETTINGS_bsec_state) {
+        NVSCHECK(nvs_set_blob(storage, "bsec_state", (void*) g_Settings.bsec_state, BSEC_MAX_STATE_BLOB_SIZE));
+    }
 }
 
 uint16_t app_get_bootcount()

main/settings.h

@@ -10,6 +10,7 @@
 #include <nvs.h>
 #include <driver/uart.h>
 #include <sdkconfig.h>
+#include <bsec2.h>
 
 #define CONSOLE_TELNET_PORT CONFIG_CONSOLE_TELNET_PORT
 #define CONSOLE_PW_LEN CONFIG_CONSOLE_PW_LEN
@@ -35,6 +36,7 @@ extern nvs_handle g_nvs_storage;
     X(bool          , ntp_enable     ,            , 1        , true  , bool , &) \
     X(char          , ntp_srv       ,[NTP_SRV_LEN], DEF_NTP_SRV , false, none , ) \
     X(uint16_t      , co2_calib     ,[5], {}, false, none , ) \
+    X(uint8_t       , bsec_state     ,[BSEC_MAX_STATE_BLOB_SIZE], {}, false, none , ) \
     X(bool          , dhcp_wd_enable ,            , 1        , true  , bool , &) \
     X(bool          , dhcp_enable    ,            , 1        , true  , bool , &) \
     X(uint32_t      , static_ip      ,          , 0          , true  , u32  , &) \

main/voc_sensor.c

@@ -23,6 +23,7 @@ static const char *TAG = "voc";
 #include "bme68x_defs.h"
 #include "bsec2.h"
 #include "periph_init.h"
+#include "settings.h"
 
 struct sensor_itf {
     uint8_t dev_addr;
@@ -30,7 +31,7 @@ struct sensor_itf {
 
 static struct sensor_itf gas_sensor_intf = {};
 static struct bme68x_dev gas_sensor = {};
-static struct bsec2 gas_sensor_bsec = {};
+static struct bsec2 hBsec = {};
 
 void bsec2_errormsg(const char *msg) {
     ESP_LOGE("BSEC", "%s", msg);
@@ -103,7 +104,7 @@ static esp_err_t voc_init(void) {
     int8_t rslt;
     gas_sensor_intf.dev_addr = BME68X_I2C_ADDR_LOW;
     gas_sensor.intf_ptr = &gas_sensor_intf;
-    gas_sensor.amb_temp = 25; // TODO set this from senseair!
+    gas_sensor.amb_temp = 25;
     gas_sensor.intf = BME68X_I2C_INTF;
     gas_sensor.read = user_i2c_read;
     gas_sensor.write = user_i2c_write;
@@ -243,7 +244,7 @@ void voc_read_task(void *param) {
         goto abort;
     }
 
-    int rv = bsec2_init(&gas_sensor_bsec, &gas_sensor);
+    int rv = bsec2_init(&hBsec, &gas_sensor);
     if (rv != 0) {
         ESP_LOGE(TAG, "Error in bsec init: %d", rv);
         goto abort;
@@ -267,7 +268,7 @@ void voc_read_task(void *param) {
             BSEC_OUTPUT_RUN_IN_STATUS,
     };
 
-    rv = bsec2_updateSubscription(&gas_sensor_bsec,
+    rv = bsec2_updateSubscription(&hBsec,
                                   sensorList,
                                   sizeof(sensorList) / sizeof(bsecSensor),
                                   BSEC_SAMPLE_RATE_LP);
@@ -277,21 +278,35 @@ void voc_read_task(void *param) {
         goto abort;
     }
 
-    bsec2_attachCallback(&gas_sensor_bsec, new_data_callback);
+    bsec2_attachCallback(&hBsec, new_data_callback);
 
     ESP_LOGI(TAG, "BSEC library version %d.%d.%d.%d",
-             gas_sensor_bsec.version.major,
-             gas_sensor_bsec.version.minor,
-             gas_sensor_bsec.version.major_bugfix,
-             gas_sensor_bsec.version.minor_bugfix);
+             hBsec.version.major,
+             hBsec.version.minor,
+             hBsec.version.major_bugfix,
+             hBsec.version.minor_bugfix);
 
-    // TODO add bsec state persistence to NVS at some landmark intervals, e.g. 1 day
-    // TODO periodic updating of sensor ambient temp
+    const uint32_t state_persist_time_ticks = 12 * 3600 * 1000;
+    _Static_assert(configTICK_RATE_HZ == 1000, "1kHz tick");
+    uint32_t last_state_persist = xTaskGetTickCount();
+
+    ESP_LOGI(TAG, "Restore BSEC state");
+    bsec2_setState(&hBsec, g_Settings.bsec_state);
 
     while (1) {
-        rv = bsec2_run(&gas_sensor_bsec);
+        rv = bsec2_run(&hBsec);
         if (false == rv) {
             ESP_LOGE(TAG, "Error in bsec run!");
+        } else {
+            uint32_t tickNow = xTaskGetTickCount();
+            uint32_t elapsed = tickNow - last_state_persist;
+            if (elapsed > state_persist_time_ticks) {
+                ESP_LOGI(TAG, "Read & persist BSEC state");
+                last_state_persist = tickNow;
+                if (bsec2_getState(&hBsec, g_Settings.bsec_state)) {
+                    settings_persist(SETTINGS_bsec_state);
+                }
+            }
         }
         vTaskDelay(pdMS_TO_TICKS(100));
     }