/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2021 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usart.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <stdbool.h>
#include <string.h>
#include <ctype.h>
#include <stdio.h>
#include <stdarg.h>
#include <usart.h>
#include <ctype.h>
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define UART_TIMEOUT 10
#define BUF_SIZE 1024
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
struct RingBuffer {
char data[BUF_SIZE];
uint8_t head;
uint8_t tail;
bool empty;
};
typedef struct RingBuffer RingBuffer;
static void buf_init(RingBuffer *buf) {
buf->head = 0;
buf->tail = 0;
buf->empty = true;
}
static void buf_push(RingBuffer *buf, char *el) {
uint64_t size = strlen(el);
if (buf->head + size + 1 > BUF_SIZE) {
buf->head = 0;
}
strcpy(&buf->data[buf->head], el);
// buf->data[buf->head] = el;
buf->head += size + 1;
if (buf->head == BUF_SIZE) {
buf->head = 0;
}
buf->empty = false;
}
static bool buf_pop(RingBuffer *buf, /* out */ char *el) {
if (buf->empty) {
return false;
}
uint64_t size = strlen(&buf->data[buf->tail]);
strcpy(el, &buf->data[buf->tail]);
buf->tail += size + 1;
if (buf->tail == BUF_SIZE || buf->tail == '\0') {
buf->tail = 0;
}
if (buf->tail == buf->head) {
buf->empty = true;
}
return true;
}
static struct RingBuffer ringBuffer;
static struct RingBuffer ringBufferTx;
static char el[2] = {"\0\0"};
static bool is_button_active() {
return HAL_GPIO_ReadPin(GPIOC, GPIO_PIN_15) == GPIO_PIN_RESET;
}
static void set_green_led(bool on) { HAL_GPIO_WritePin(GPIOD, GPIO_PIN_13, on ? GPIO_PIN_SET : GPIO_PIN_RESET); }
static void set_yellow_led(bool on) { HAL_GPIO_WritePin(GPIOD, GPIO_PIN_14, on ? GPIO_PIN_SET : GPIO_PIN_RESET); }
static void set_red_led(bool on) { HAL_GPIO_WritePin(GPIOD, GPIO_PIN_15, on ? GPIO_PIN_SET : GPIO_PIN_RESET); }
struct ButtonState {
bool is_pressed;
bool signaled;
uint32_t press_start_time;
};
static bool update_button_state(struct ButtonState *state) {
if (state->is_pressed) {
state->is_pressed = is_button_active();
if (state->signaled) {
return false;
}
if ((HAL_GetTick() - state->press_start_time) > 20 /* ms */) {
state->signaled = true;
return true;
}
return false;
}
if (is_button_active()) {
state->press_start_time = HAL_GetTick();
state->is_pressed = true;
state->signaled = false;
}
return false;
}
struct Status {
bool interrupt_enable;
};
static struct Status status;
bool transmit_busy = false;
void enable_interrupt(struct Status *status) {
HAL_NVIC_EnableIRQ(USART6_IRQn);
status->interrupt_enable = true;
}
void disable_interrupt(struct Status *status) {
HAL_UART_AbortReceive(&huart6);
HAL_NVIC_DisableIRQ(USART6_IRQn);
status->interrupt_enable = false;
}
void transmit_uart(const struct Status *status, char *buf, size_t size) {
if (status->interrupt_enable) {
if (transmit_busy) {
buf_push(&ringBufferTx, buf);
} else {
HAL_UART_Transmit_IT(&huart6, buf, size);
transmit_busy = true;
}
return;
}
HAL_UART_Transmit(&huart6, buf, size, 100);
}
void transmit_uart_nl(const struct Status *status, char *buf, size_t size) {
transmit_uart(status, buf, size);
transmit_uart(status, "\r\n", 2);
}
void receive_uart(const struct Status *status) {
if (status->interrupt_enable) {
HAL_UART_Receive_IT(&huart6, el, sizeof(char));
return;
}
HAL_StatusTypeDef stat = HAL_UART_Receive(&huart6, el, sizeof(char), 0);
switch (stat) {
case HAL_OK: {
buf_push(&ringBuffer, el);
transmit_uart(status, el, 1);
break;
}
case HAL_ERROR:
case HAL_BUSY:
case HAL_TIMEOUT:
break;
}
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) {
buf_push(&ringBuffer, el);
transmit_uart(&status, el, 1);
}
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart) {
char buf[1024];
if (buf_pop(&ringBufferTx, buf)) {
HAL_UART_Transmit_IT(&huart6, buf, strlen(buf));
} else {
transmit_busy = false;
}
}
enum ValueDefenition {
LeftValue,
LeftValueWithOperand,
RightValue,
RightValueWithEquals,
ResultValue,
ErrorValue
};
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_USART6_UART_Init();
/* USER CODE BEGIN 2 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
char interrupt_enabled_msg[] = {"Interrupts is on"};
char interrupt_disabled_msg[] = {"Interrupts is off"};
char error_msg[] = {"\r\nError occurs\n"};
struct ButtonState buttonState = {.press_start_time = 0, .signaled = false, .is_pressed = false};
enable_interrupt(&status);
buf_init(&ringBuffer);
uint32_t arg1 = 0;
uint32_t arg2 = 0;
int64_t res = 0;
char res_str [8];
char op;
enum ValueDefenition exprState = LeftValue;
set_red_led(false);
while (1) {
if (update_button_state(&buttonState)) {
if (status.interrupt_enable) {
disable_interrupt(&status);
transmit_uart_nl(&status, interrupt_disabled_msg, sizeof(interrupt_disabled_msg));
} else {
enable_interrupt(&status);
transmit_uart_nl(&status, interrupt_enabled_msg, sizeof(interrupt_enabled_msg));
}
}
receive_uart(&status);
char c[2];
if ((exprState != ResultValue && exprState != ErrorValue) && !buf_pop(&ringBuffer, c)) {
continue;
}
switch (exprState) {
case LeftValue: {
if (!isdigit(c[0])) {
exprState = ErrorValue;
break;
}
exprState = LeftValueWithOperand;
set_red_led(false);
arg1 = arg1 * 10 + (c[0] - 48);
uint16_t new_arg1 = (uint16_t) arg1;
if (arg1 != new_arg1) {
exprState = ErrorValue;
}
break;
}
case LeftValueWithOperand: {
if (!isdigit(c[0])) {
switch (c[0]) {
case '+':
case '-':
case '*':
case '/': {
op = c[0];
exprState = RightValue;
break;
}
default:
exprState = ErrorValue;
break;
}
break;
}
arg1 = arg1 * 10 + (c[0] - 48);
uint16_t new_arg1 = (uint16_t) arg1;
if (arg1 != new_arg1) {
exprState = ErrorValue;
}
break;
}
case RightValue: {
if (!isdigit(c[0])) {
exprState = ErrorValue;
break;
}
exprState = RightValueWithEquals;
arg2 = arg2 * 10 + (c[0] - 48);
uint16_t new_arg2 = (uint16_t) arg2;
if (arg2 != new_arg2) {
exprState = ErrorValue;
}
break;
}
case RightValueWithEquals: {
if (!isdigit(c[0])) {
if (c[0] == '=') {
exprState = ResultValue;
} else {
exprState = ErrorValue;
}
break;
}
arg2 = arg2 * 10 + (c[0] - 48);
uint16_t new_arg2 = (uint16_t) arg2;
if (arg2 != new_arg2) {
exprState = ErrorValue;
}
break;
}
case ResultValue: {
int32_t arg1_c = arg1;
int32_t arg2_c = arg2;
switch (op) {
case '+':
res = arg1_c + arg2_c;
break;
case '-':
res = arg1_c - arg2_c;
break;
case '*':
res = arg1_c * arg2_c;
break;
case '/':{
if (arg2_c == 0) {
exprState = ErrorValue;
continue;
} else {
res = arg1_c / arg2_c;
}
break;
}
default:
break;
}
int16_t actual_res = res;
if (actual_res != res) {
exprState = ErrorValue;
break;
}
sprintf(res_str, "%d", res);
transmit_uart_nl(&status, res_str, strlen(res_str));
arg1 = 0;
arg2 = 0;
res = 0;
exprState = LeftValue;
break;
}
case ErrorValue: {
arg1 = 0;
arg2 = 0;
res = 0;
set_red_led(true);
transmit_uart_nl(&status, error_msg, sizeof(error_msg));
exprState = LeftValue;
break;
}
default:
break;
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler();
}
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/