Convert ultrasonic flight time to distance value

inc/ultrasonic_driver.h

@@ -7,6 +7,9 @@
 
 #include "gd32e23x.h"
 
+#define ULTRASONIC_CYCLES   0x05U
+#define ULTRASONIC_TRAN_US  100  // (ms)
+
 #define LED_PORT            GPIOA
 #define LED_PIN             GPIO_PIN_9
 #define LED_RCU             RCU_GPIOA
@@ -14,22 +17,39 @@
 #define LED_TIMER           TIMER5
 #define LED_IRQ             TIMER5_IRQn
 
-#define USART_RCU           RCU_USART0
+#define USART_RCU            RCU_USART0
-#define USART_GPIO_RCU      RCU_GPIOA
+#define USART_GPIO_RCU       RCU_GPIOA
-#define USARET_GPIO_PORT    GPIOA
+#define USARET_GPIO_PORT     GPIOA
-#define USART_TX_PIN        GPIO_PIN_2
+#define USART_TX_PIN         GPIO_PIN_2
-#define USART_RX_PIN        GPIO_PIN_3
+#define USART_RX_PIN         GPIO_PIN_3
-#define USART0_PHY          USART0
+#define USART0_PHY           USART0
-#define USART_BAUDRATE      115200U
+#define USART_BAUDRATE       115200U
 
-#define US_TRAN_GPIO_RCU    RCU_GPIOB
+#define US_TRAN_GPIO_RCU     RCU_GPIOB
-#define US_TRAN_GPIO_PORT   GPIOB
+#define US_TRAN_GPIO_PORT    GPIOB
-#define US_TRAN_PIN         GPIO_PIN_1
+#define US_TRAN_PIN          GPIO_PIN_1
-#define US_TRAN_AF          GPIO_AF_0
+#define US_TRAN_AF           GPIO_AF_0
 
-#define US_TRAN_RCU         RCU_TIMER13
+#define US_TRAN_RCU          RCU_TIMER13
-#define US_TRAN_TIMER       TIMER13
+#define US_TRAN_TIMER        TIMER13
-#define US_TRAN_CH          TIMER_CH_0
+#define US_TRAN_CH           TIMER_CH_0
+
+#define US_TRAN_DELAY_RCU     RCU_TIMER15
+#define US_TRAN_DELAY_TIMER   TIMER15
+
+#define US_FB_GPIO_RCU       RCU_GPIOA
+#define US_FB_EXTI_RCU       RCU_CFGCMP
+#define US_FB_GPIO_PORT      GPIOA
+#define US_FB_GPIO_PIN       GPIO_PIN_0
+#define US_FB_EXTI_IRQ       EXTI0_1_IRQn
+#define US_FB_GPIO_EXTI      EXTI_0
+
+#define US_ECHO_RCU          RCU_TIMER16
+#define US_ECHO_TIMER        TIMER16
+#define US_ECHO_CH           TIMER_CH_0
+
+#define SOUND_SPEED         340      // m/s
+#define TIME_CORRECTION_US  250
 
 void led_config(void);
 void usart_config(void);
@@ -42,4 +62,6 @@ void ultrasonic_transmit_delay(const uint16_t micro_second);
 void recevice_exti_config(void);
 void ultrasonic_echo_timer_config(void);
 
+uint16_t calculate_distance(uint32_t us_value);
+
 #endif //ULTRASONIC_DRIVER_H

src/main.c

@@ -12,10 +12,8 @@
 
 #include "ultrasonic_driver.h"
 
-#define ULTRASONIC_CYCLES     0x05U
-#define ULTRASONIC_TRAN_US    50  // (ms)
-
 extern uint32_t capture_value;
+uint16_t distance_uint16;
 
 /*!
     \brief      main function
@@ -30,13 +28,13 @@ int main(void)
     /* configure ultrasonic board hardware */
     ultrasonic_transmit_config();
 
-
+    ultrasonic_transmit_delay(TIME_CORRECTION_US);
-
-    /* ---------- debug start ---------- */
-    ultrasonic_transmit_delay(250);
     recevice_exti_config();
     ultrasonic_echo_timer_config();
 
+    /* ---------- debug start ---------- */
+
+
 
 
     /* ---------- debug end ---------- */
@@ -55,6 +53,8 @@ int main(void)
         // printf("Send ultra sonic driver signal!\r\n");
     delay_ms(2);
         printf("cap_val:%ld\n", capture_value);
+        distance_uint16 = calculate_distance(capture_value);
+        printf("Distance:%d\n", distance_uint16);
     }
 }
 

src/ultrasonic_driver.c

@@ -122,10 +122,8 @@ void ultrasonic_pwm_out_cycles(const uint8_t cycles) {
 }
 
 void ultrasonic_transmit_delay(const uint16_t micro_second) {
-    rcu_periph_clock_enable(RCU_GPIOA);
+    rcu_periph_clock_enable(US_TRAN_DELAY_RCU);
-
+    timer_deinit(US_TRAN_DELAY_TIMER);
-    rcu_periph_clock_enable(RCU_TIMER15);
-    timer_deinit(TIMER15);
 
     timer_parameter_struct timer_initpara;
     timer_struct_para_init(&timer_initpara);
@@ -135,31 +133,31 @@ void ultrasonic_transmit_delay(const uint16_t micro_second) {
     timer_initpara.period            =micro_second - 1;
     timer_initpara.clockdivision     =TIMER_CKDIV_DIV1;
     timer_initpara.repetitioncounter =0;
-    timer_init(TIMER15, &timer_initpara);
+    timer_init(US_TRAN_DELAY_TIMER, &timer_initpara);
 
-    timer_auto_reload_shadow_enable(TIMER15);  //使能自动影子重载
+    timer_auto_reload_shadow_enable(US_TRAN_DELAY_TIMER);  //使能自动影子重载
-    timer_interrupt_enable(TIMER15, TIMER_INT_UP);  // 使能自动重载中断
+    timer_interrupt_enable(US_TRAN_DELAY_TIMER, TIMER_INT_UP);  // 使能自动重载中断
     nvic_irq_enable(TIMER15_IRQn, 1U);
 }
 
 void recevice_exti_config(void) {
-    rcu_periph_clock_enable(RCU_GPIOA);
+    rcu_periph_clock_enable(US_FB_GPIO_RCU);
-    rcu_periph_clock_enable(RCU_CFGCMP);
+    rcu_periph_clock_enable(US_FB_EXTI_RCU);
 
-    gpio_mode_set(GPIOA, GPIO_MODE_INPUT, GPIO_PUPD_NONE, GPIO_PIN_0);
+    gpio_mode_set(US_FB_GPIO_PORT, GPIO_MODE_INPUT, GPIO_PUPD_NONE, US_FB_GPIO_PIN);
-    nvic_irq_enable(EXTI0_1_IRQn, 0U);
+    nvic_irq_enable(US_FB_EXTI_IRQ, 0U);
     syscfg_exti_line_config(EXTI_SOURCE_GPIOA, EXTI_SOURCE_PIN0);
 
-    exti_init(EXTI_0, EXTI_INTERRUPT, EXTI_TRIG_FALLING);
+    exti_init(US_FB_GPIO_EXTI, EXTI_INTERRUPT, EXTI_TRIG_FALLING);
-    exti_flag_clear(EXTI_0);
+    exti_flag_clear(US_FB_GPIO_EXTI);
 
     // exti_interrupt_enable(EXTI_0);
 }
 
 void ultrasonic_echo_timer_config(void)
 {
-    rcu_periph_clock_enable(RCU_TIMER16);
+    rcu_periph_clock_enable(US_ECHO_RCU);
-    timer_deinit(TIMER16);
+    timer_deinit(US_ECHO_TIMER);
 
     timer_parameter_struct timer_initpara;
     timer_struct_para_init(&timer_initpara);
@@ -169,7 +167,7 @@ void ultrasonic_echo_timer_config(void)
     timer_initpara.period            =59999;
     timer_initpara.clockdivision     =TIMER_CKDIV_DIV1;
     timer_initpara.repetitioncounter =0;
-    timer_init(TIMER16, &timer_initpara);
+    timer_init(US_ECHO_TIMER, &timer_initpara);
 
     timer_ic_parameter_struct timer_icinitpara;
     timer_channel_input_struct_para_init(&timer_icinitpara);
@@ -177,7 +175,17 @@ void ultrasonic_echo_timer_config(void)
     timer_icinitpara.icselection = TIMER_IC_SELECTION_INDIRECTTI;
     timer_icinitpara.icprescaler = TIMER_IC_PSC_DIV1;
     timer_icinitpara.icfilter = 0x03; // 设置滤波器
-    timer_input_capture_config(TIMER16, TIMER_CH_0, &timer_icinitpara);
+    timer_input_capture_config(US_ECHO_TIMER, US_ECHO_CH, &timer_icinitpara);
-
+}
-    // timer_enable(TIMER16);
+
+uint16_t calculate_distance(uint32_t us_value) {
+    uint16_t distace = (TIME_CORRECTION_US + us_value) * 17;
+    /*
+     *  (TIME_CORRECTION_US + us_value) * 340 m/s
+     *  -----------------------------------------
+     *                  1000 000
+     *  ----------------------------------------------
+     *                          2
+     */
+    return distace;
 }