From 1341a1000acaddd05f44c24779a52e706b032775 Mon Sep 17 00:00:00 2001
From: Sven Luethi <dev@svenluthi.com>
Date: Sun, 11 Aug 2024 11:20:15 +0200
Subject: [PATCH] modified:   main/include/sht31.h modified:   main/src/main.c
 modified:   main/src/sht31.c Fix floating point issue with Sensor readouts

---
 firmware/main/include/sht31.h |  1 -
 firmware/main/src/main.c      | 19 ++++++++++++----
 firmware/main/src/sht31.c     | 43 -----------------------------------
 3 files changed, 15 insertions(+), 48 deletions(-)

diff --git a/firmware/main/include/sht31.h b/firmware/main/include/sht31.h
index 201597c..230d783 100644
--- a/firmware/main/include/sht31.h
+++ b/firmware/main/include/sht31.h
@@ -19,7 +19,6 @@ float sht31_get_humidity(void);
 float sht31_get_temperature(void);
 
 esp_err_t sht31_read_temp_hum(float *temperature, float *humidity);
-esp_err_t sht31_read_temp_hum_int(int *temperature, int *humidity);
 
 #ifdef __cplusplus
 }
diff --git a/firmware/main/src/main.c b/firmware/main/src/main.c
index 1646907..9420f05 100644
--- a/firmware/main/src/main.c
+++ b/firmware/main/src/main.c
@@ -36,18 +36,29 @@ static void wifi_init(void) {
 }
 */
 
+static void split_float(float num, int *int_part, float *dec_part) {
+    // Extract the integer part
+    *int_part = (float)((int)num);
+    
+    // Calculate the fractional part by subtracting the integer part from the original number
+    *dec_part = num - *int_part;
+}
+
+
 void sensor_tester(void)
 {
     ESP_ERROR_CHECK(sht31_init());
 
     //float temperature, humidity;
-    int temperature, humidity;
+    float temperature, humidity, temp_dec_part, hum_dec_part;
+    int temp_int_part, hum_int_part;
 
     while (1) {
-        //if (sht31_read_temp_hum(&temperature, &humidity) == ESP_OK) {
-        if (sht31_read_temp_hum_int(&temperature, &humidity) == ESP_OK) {
+        if (sht31_read_temp_hum(&temperature, &humidity) == ESP_OK) {
+	    split_float(temperature, &temp_int_part, &temp_dec_part);
+	    split_float(humidity, &hum_int_part, &hum_dec_part);
             //ESP_LOGI(TAG, "Temperature: %.2f°C, Humidity: %.2f%%", temperature, humidity);
-            ESP_LOGI(TAG, "Temperature: %i°C, Humidity: %i%%", temperature, humidity);
+            ESP_LOGI(TAG, "Temperature: %i.%i°C, Humidity: %i.%i%%", temp_int_part, (int)(temp_dec_part*1000), hum_int_part, (int)(hum_dec_part*1000));
         } else {
             ESP_LOGE(TAG, "Failed to read from SHT31 sensor");
         }
diff --git a/firmware/main/src/sht31.c b/firmware/main/src/sht31.c
index b6cd0fb..229ec34 100644
--- a/firmware/main/src/sht31.c
+++ b/firmware/main/src/sht31.c
@@ -100,46 +100,3 @@ esp_err_t sht31_read_temp_hum(float *temperature, float *humidity)
     return ESP_OK;
 }
 
-esp_err_t sht31_read_temp_hum_int(int *temperature, int *humidity)
-{
-    uint8_t data[6];
-    i2c_cmd_handle_t cmd = i2c_cmd_link_create();
-
-    // Send the measurement command
-    i2c_master_start(cmd);
-    i2c_master_write_byte(cmd, (SENSOR_ADDR << 1) | I2C_MASTER_WRITE, true);
-    i2c_master_write_byte(cmd, SHT31_MEASURE_CMD_HIGHREP >> 8, true);
-    i2c_master_write_byte(cmd, SHT31_MEASURE_CMD_HIGHREP & 0xFF, true);
-    i2c_master_stop(cmd);
-    esp_err_t ret = i2c_master_cmd_begin(I2C_NUM_0, cmd, 1000 / portTICK_RATE_MS);
-    i2c_cmd_link_delete(cmd);
-    if (ret != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to send command to SHT31");
-        return ret;
-    }
-
-    vTaskDelay(500 / portTICK_RATE_MS);
-
-    // Request 6 bytes of data from the sensor
-    cmd = i2c_cmd_link_create();
-    i2c_master_start(cmd);
-    i2c_master_write_byte(cmd, (SENSOR_ADDR << 1) | I2C_MASTER_READ, true);
-    i2c_master_read(cmd, data, sizeof(data) - 1, I2C_MASTER_ACK);
-    i2c_master_read_byte(cmd, data + sizeof(data) - 1, I2C_MASTER_NACK);
-    i2c_master_stop(cmd);
-    ret = i2c_master_cmd_begin(I2C_NUM_0, cmd, 1000 / portTICK_RATE_MS);
-    i2c_cmd_link_delete(cmd);
-    if (ret != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to read data from SHT31");
-        return ret;
-    }
-
-    // Process the data
-    uint16_t t = (data[0] << 8) | data[1];
-    uint16_t h = (data[3] << 8) | data[4];
-
-    *temperature = -45 + 175 * ((float)t / 65535.0);
-    *humidity = 100 * ((float)h / 65535.0);
-
-    return ESP_OK;
-}