// --- GPIO HAL Implementation (Example for a hypothetical MCU) --- voidHAL_GPIO_Init(GPIO_InitTypeDef *GPIO_InitStruct) { // ... Hardware specific GPIO initialization code based on GPIO_InitStruct // Example: Set GPIO pin direction, pull-up/down, etc. if (GPIO_InitStruct->Mode == GPIO_MODE_OUTPUT) { // Configure GPIO pin as output } elseif (GPIO_InitStruct->Mode == GPIO_MODE_INPUT) { // Configure GPIO pin as input } // ... and so on for different modes and configurations }
void HAL_GPIO_WritePin(GPIO_PinTypeDef Pin, bool PinState) { // ... Hardware specific GPIO pin write code // Example: Set GPIO pin high or low if (PinState) { // Set GPIO pin HIGH } else { // Set GPIO pin LOW } }
bool HAL_GPIO_ReadPin(GPIO_PinTypeDef Pin) { // ... Hardware specific GPIO pin read code // Example: Read GPIO pin state (high or low) // ... return true if pin is HIGH, false if pin is LOW returnfalse; // Placeholder - Replace with actual hardware read }
// --- ADC HAL Implementation (Example) --- voidHAL_ADC_Init(ADC_InitTypeDef *ADC_InitStruct) { // ... Hardware specific ADC initialization code based on ADC_InitStruct // Example: Enable ADC clock, configure ADC resolution, etc. // ... Configure ADC channel based on ADC_InitStruct->Channel }
uint16_tHAL_ADC_ReadChannel(ADC_ChannelTypeDef Channel) { // ... Hardware specific ADC channel read code // Example: Start ADC conversion, wait for completion, read ADC data register // ... return the ADC reading (12-bit, 16-bit, etc. depending on ADC resolution) return0; // Placeholder - Replace with actual hardware ADC read }
// ... Implementations for other HAL functions (SPI, I2C, UART, Timer, etc.) // ... based on the specific MCU and peripherals used in the project.
// Example Timer HAL delay function using a basic loop (not accurate, for demonstration only) voidHAL_TIM_DelayMs(uint32_t Delay) { volatileuint32_t count; for (count = 0; count < Delay * 1000; count++) { // Adjust multiplier for approximate millisecond delay __asm__("nop"); // No operation - simple delay } }
#include"freertos_tasks.h" #include"board_config.h" #include"hardware_hal.h" #include"middleware_services.h"// Include middleware services
#include<stdio.h>// For sprintf
// --- Temperature Task --- voidTemperatureTask(void *pvParameters) { TickType_t xLastWakeTime; const TickType_t xFrequency = pdMS_TO_TICKS(1000); // Task frequency: 1 second
xLastWakeTime = xTaskGetTickCount();
for (;;) { vTaskDelayUntil(&xLastWakeTime, xFrequency);
uint16_t adc_value = HAL_ADC_ReadChannel(TEMP_SENSOR_ADC_CHANNEL); float temperature_celsius = ConvertAdcToCelsius(adc_value); // Middleware service to convert ADC to Celsius
printf("Temperature: %.2f C\r\n", temperature_celsius); // Print temperature via UART for debugging
// ... Send temperature data to other tasks (e.g., DisplayTask, DataStorageTask) using message queues or other IPC mechanisms TemperatureData_t tempData; tempData.temperature = temperature_celsius; SendTemperatureData(&tempData); // Middleware service to send temperature data } }
for (;;) { vTaskDelayUntil(&xLastWakeTime, xFrequency);
// Receive temperature data from TemperatureTask (using message queue or other IPC) if (ReceiveTemperatureData(&receivedTempData)) { // Middleware service to receive temperature data sprintf(temperature_str, "Temp: %.1f C", receivedTempData.temperature); // ... Use graphics library (e.g., LittlevGL, emWin) to update temperature display on LCD // Example: Display_WriteString(temperature_str, x_position, y_position, font); // Hypothetical display function printf("Displaying: %s\r\n", temperature_str); // Print for debugging } else { // No new temperature data received, handle error or do nothing printf("No temperature data received for display\r\n"); } } }
// --- Data Storage Task (Example - simplified data logging task) --- voidDataStorageTask(void *pvParameters) { TickType_t xLastWakeTime; const TickType_t xFrequency = pdMS_TO_TICKS(5000); // Data logging frequency: 5 seconds
for (;;) { vTaskDelayUntil(&xLastWakeTime, xFrequency);
if (ReceiveTemperatureData(&receivedTempData)) { // Middleware service to receive temperature data // ... Format data for storage (e.g., timestamp, temperature) char log_entry[50]; sprintf(log_entry, "Timestamp: %lu, Temp: %.2f C\r\n", xTaskGetTickCount(), receivedTempData.temperature);
// ... Use file system middleware to append data to a log file // Example: FileSystem_AppendToFile("data.log", log_entry); // Hypothetical file system function printf("Logging: %s", log_entry); // Print for debugging } else { // No new temperature data received, handle error or do nothing printf("No temperature data received for logging\r\n"); } } }
// --- Temperature Data Structure for IPC --- typedefstruct { float temperature; // ... other temperature related data } TemperatureData_t;
// --- Temperature Data Queue --- extern QueueHandle_t xTemperatureDataQueue;
// --- Temperature Data Service Functions --- floatConvertAdcToCelsius(uint16_t adc_value); voidSendTemperatureData(TemperatureData_t *pData); boolReceiveTemperatureData(TemperatureData_t *pData);
// ... Declare other middleware service functions (e.g., file system, graphics, networking services)
// --- Temperature Data Queue (Global - Initialize in main.c) --- QueueHandle_t xTemperatureDataQueue;
// --- Temperature Data Service Implementations --- floatConvertAdcToCelsius(uint16_t adc_value) { // ... Implement ADC value to Celsius conversion formula // Example: Assuming linear relationship and known ADC range and temperature range float vref = 3.3f; // Reference voltage uint16_t adc_max_value = 4095; // 12-bit ADC float temp_range = 100.0f; // Example temperature range (0-100 C)
float voltage = (float)adc_value * vref / adc_max_value; float temperature = (voltage / vref) * temp_range; // Simplified linear conversion
return temperature; }
voidSendTemperatureData(TemperatureData_t *pData) { // Send temperature data to the temperature data queue xQueueSend(xTemperatureDataQueue, pData, 0); // Non-blocking send }
boolReceiveTemperatureData(TemperatureData_t *pData) { // Receive temperature data from the temperature data queue if (xQueueReceive(xTemperatureDataQueue, pData, 0) == pdTRUE) { // Non-blocking receive returntrue; // Data received } else { returnfalse; // No data received } }
// ... Implement other middleware service functions (e.g., file system, graphics, networking services) // ... These implementations would typically use external libraries or custom code for each service.
// --- Error Handling (Example - Simple Error Handler) --- voidvApplicationMallocFailedHook(void) { /* vApplicationMallocFailedHook() will only be called if * configUSE_MALLOC_FAILED_HOOK is set to 1 in FreeRTOSConfig.h. It is a hook * function that will get called if a call to pvPortMalloc() fails. * pvPortMalloc() is called internally by the kernel whenever a task, queue, * timer or semaphore is created. It is also called by various parts of the * demo application. If heap_1.c or heap_2.c are used, then the size of the * heap available to pvPortMalloc() is defined by configTOTAL_HEAP_SIZE in * FreeRTOSConfig.h, and the xPortGetFreeHeapSize() API function can be used * to query the size of free heap space that remains (although it does not * provide real time information). */ taskDISABLE_INTERRUPTS(); printf("ERROR: Memory allocation failed!\r\n"); for (;;); // Infinite loop to halt execution }
voidvApplicationStackOverflowHook(TaskHandle_t xTask, char *pcTaskName) { (void)pcTaskName; (void)xTask; /* Run time stack overflow checking is performed if * configCHECK_FOR_STACK_OVERFLOW is defined to 1 or 2 in FreeRTOSConfig.h. * This hook function is called if a stack overflow is detected. */ taskDISABLE_INTERRUPTS(); printf("ERROR: Stack overflow in task: %s\r\n", pcTaskName); for (;;); // Infinite loop to halt execution }
voidvApplicationIdleHook(void) { /* vApplicationIdleHook() will only be called if configUSE_IDLE_HOOK is set * to 1 in FreeRTOSConfig.h. It will be called on each iteration of the idle * task. It is essential that code added to this hook function never attempts * to block in any way (for example, to attempt to obtain a semaphore). If * you wish to schedule other tasks on the idle task, then consider using the * idle task priority to lower your task priority. */ // ... Optional: Low power mode entry in idle hook if needed // Example: EnterLowPowerMode(); }
voidvApplicationTickHook(void) { /* This function will be called by each tick interrupt if * configUSE_TICK_HOOK is set to 1 in FreeRTOSConfig.h. User code can be * added here, but the tick hook handler must be very short, and must not * call any API functions that might block. A tick hook handler is a good * place to monitor for stack overflow. */ // ... Optional: System tick processing if needed (very minimal) }
