v2.1.0

added business logic

Author: git-user-cpp

Core/Inc/bl.h

@@ -0,0 +1,43 @@
+/*
+ * aht20_driver_stm32f446ret
+ * driver for aht20 temperature and humidity sensor
+ * Copyright (C) 2025 Andrew Kushyk
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "main.h"
+
+/*
+ * return statuses for business logic
+ */
+typedef enum {
+	BL_STATUS_OK = 1,
+	BL_STATUS_RUN_FAILED,
+} bl_status_t;
+
+/*
+ * runs calibration check. if wasn't calibrated, calibrates the sensor
+ */
+bl_status_t bl_run_sensor(I2C_HandleTypeDef *hi2c, UART_HandleTypeDef *huart);
+
+/*
+ * processes and calculates sensor data
+ */
+bl_status_t bl_process_sensor_data(I2C_HandleTypeDef *hi2c, UART_HandleTypeDef *huart);
+
+/*
+ * transmits formatted data to UART
+ */
+void bl_uart_transmit_sensor_data(UART_HandleTypeDef *huart);

Core/Inc/main.h

@@ -47,6 +47,9 @@ extern "C" {
 /* Exported macro ------------------------------------------------------------*/
 /* USER CODE BEGIN EM */
 
+/* remove the comment to enable debugging messages via UART */
+//#define DEBUGGING
+
 /* USER CODE END EM */
 
 /* Exported functions prototypes ---------------------------------------------*/

Core/Inc/utils.h

@@ -21,7 +21,12 @@
 #include <aht20.h>
 #include "main.h"
 
+#ifdef DEBUGGING
 /*
  * prints error message via UART
  */
 void print_error(UART_HandleTypeDef *huart, aht20_status_t status);
+#endif
+
+/* transmits data to UART */
+void transmit_data(UART_HandleTypeDef *huart, float humidity, float temperature_c, float temperature_f);

Core/Src/bl.c

@@ -0,0 +1,72 @@
+/*
+ * aht20_driver_stm32f446ret
+ * driver for aht20 temperature and humidity sensor
+ * Copyright (C) 2025 Andrew Kushyk
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "bl.h"
+#include "aht20.h"
+#include "utils.h"
+
+/*
+ * holds sensor data
+ */
+static aht20_data_t sensor_data = {0};
+
+/*
+ * runs calibration check. if wasn't calibrated, calibrates the sensor
+ */
+bl_status_t bl_run_sensor(I2C_HandleTypeDef *hi2c, UART_HandleTypeDef *huart) {
+	aht20_status_t status = AHT20_STATUS_OK;
+
+	status = aht20_api.aht20_validate_calibration(hi2c);
+	if (status != AHT20_STATUS_OK) {
+#ifdef DEBUGGING
+		print_error(huart, status);
+#endif
+		return BL_STATUS_RUN_FAILED;
+	}
+
+	return BL_STATUS_OK;
+}
+
+/*
+ * processes and calculates sensor data
+ */
+bl_status_t bl_process_sensor_data(I2C_HandleTypeDef *hi2c, UART_HandleTypeDef *huart) {
+	aht20_status_t status = AHT20_STATUS_OK;
+
+	status = aht20_measure(hi2c, sensor_data.measured_data, (uint16_t)sizeof(sensor_data.measured_data));
+	if (status != AHT20_STATUS_OK) {
+#ifdef DEBUGGING
+		print_error(huart, status);
+#endif
+		status = aht20_soft_reset(hi2c);
+		if (status != AHT20_STATUS_OK) {
+			return BL_STATUS_RUN_FAILED;
+		}
+	}
+
+	aht20_calculate_measurments(sensor_data.measured_data, &sensor_data.humidity, &sensor_data.temperature_c, &sensor_data.temperature_f);
+
+	return BL_STATUS_OK;
+}
+
+/*
+ * transmits formatted data to UART
+ */
+void bl_uart_transmit_sensor_data(UART_HandleTypeDef *huart) {
+	transmit_data(huart, sensor_data.humidity, sensor_data.temperature_c, sensor_data.temperature_f);
+}

Core/Src/main.c

@@ -25,7 +25,7 @@
 
 /* Private includes ----------------------------------------------------------*/
 /* USER CODE BEGIN Includes */
-#include "aht20.h"
+#include "bl.h"
 #include "utils.h"
 #include <stdio.h>
 #include <string.h>
@@ -64,18 +64,7 @@ static void MX_I2C1_Init(void);
 
 /* Private user code ---------------------------------------------------------*/
 /* USER CODE BEGIN 0 */
-/* just a wrapper for HAL_UART_Transmit*/
-void UART_Send_String(const char* str)
-{
-	HAL_UART_Transmit(&huart2, (uint8_t*)str, strlen(str), HAL_MAX_DELAY);
-}
 
-/* transmits data to UART */
-void transmit_data(float humidity, float temperature_c, float temperature_f) {
-	char data_to_display[60] = "\0";
-	sprintf(data_to_display, "Humidity: %.2f%%, Temperature: %.2fC, %.2fF\r\n", humidity, temperature_c, temperature_f);
-	HAL_UART_Transmit(&huart2, (uint8_t *)data_to_display, strlen(data_to_display), HAL_MAX_DELAY);
-}
 /* USER CODE END 0 */
 
 /**
@@ -109,39 +98,20 @@ int main(void)
 	MX_USART2_UART_Init();
 	MX_I2C1_Init();
 	/* USER CODE BEGIN 2 */
-
-	/*
-	 * Datasheet: AHT20 Product manuals
-	 * 5.4 Sensor reading process, paragraph 1
-	 */
-	aht20_status_t status = AHT20_STATUS_OK;
-
-	/* getting info about sensor calibration */
-	status = aht20_validate_calibration(&hi2c1);
-	if (status != AHT20_STATUS_OK) {
-		print_error(&huart2, status);
+	if(BL_STATUS_OK != bl_run_sensor(&hi2c1, &huart2)) {
 		return 1;
 	}
-
 	/* USER CODE END 2 */
 
 	/* Infinite loop */
 	/* USER CODE BEGIN WHILE */
-	aht20_data_t sensor_data = {0};
-
 	while (1)
 	{
-		/* triggering measuring */
-		status = aht20_measure(&hi2c1, sensor_data.measured_data, (uint16_t)sizeof(sensor_data.measured_data));
-		if (status != AHT20_STATUS_OK) {
-			print_error(&huart2, status);
-			aht20_soft_reset(&hi2c1);
-			continue;
+		if (BL_STATUS_OK != bl_process_sensor_data(&hi2c1, &huart2)) {
+			return 2;
 		}
 
-		aht20_calculate_measurments(sensor_data.measured_data, &sensor_data.humidity, &sensor_data.temperature_c, &sensor_data.temperature_f);
-		transmit_data(sensor_data.humidity, sensor_data.temperature_c, sensor_data.temperature_f);
-
+		bl_uart_transmit_sensor_data(&huart2);
 		HAL_Delay(1000);
 		/* USER CODE END WHILE */
 

Core/Src/utils.c

@@ -21,6 +21,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#ifdef DEBUGGING
 /*
  * prints error message via UART
  */
@@ -39,3 +40,11 @@ void print_error(UART_HandleTypeDef *huart, aht20_status_t status) {
     }
     HAL_UART_Transmit(huart, (uint8_t*)debug_msg, strlen(debug_msg), HAL_MAX_DELAY);
 }
+#endif
+
+/* transmits data to UART */
+void transmit_data(UART_HandleTypeDef *huart, float humidity, float temperature_c, float temperature_f) {
+	char data_to_display[60] = "\0";
+	sprintf(data_to_display, "Humidity: %.2f%%, Temperature: %.2fC, %.2fF\r\n", humidity, temperature_c, temperature_f);
+	HAL_UART_Transmit(huart, (uint8_t *)data_to_display, strlen(data_to_display), HAL_MAX_DELAY);
+}