Adding steven's ussensor code

Autonomous_Parallel_Parking/user_include/u_sensor.h

@@ -0,0 +1,19 @@
+#ifndef U_SENSOR_H
+#define U_SENSOR_H	1
+
+#include "stm32f3xx_hal.h"
+#include "hal_common_includes.h"
+
+//Initialize ultrasound sensor gpio as needed for the board we are using.
+void usensor_gpio_init(void);
+
+//Simple software delay microseconds.
+void delay_us(uint32_t n);
+
+//Measures a pulse in microseconds.
+long pulse_in(GPIO_TypeDef* echo_port);
+
+//Returns the distance from object.
+int get_sensor_dist(GPIO_TypeDef* trig_port, GPIO_TypeDef* echo_port, uint16_t trigger);
+
+#endif

Autonomous_Parallel_Parking/user_source/u_sensor.c

@@ -0,0 +1,198 @@
+/*
+  This is the main user software application
+  In this case, we have below the code necessary to set up and control usensor.
+
+ */
+#include "stm32f3xx_hal.h"
+#include "u_sensor"
+long duration;
+int distance;
+int inches;
+
+//GPIO initializations
+void usensor_gpio_init(void)
+{
+
+  GPIO_InitTypeDef GPIO_InitStruct;
+
+  /* GPIO Ports Clock Enable */
+  __HAL_RCC_GPIOF_CLK_ENABLE();
+  __HAL_RCC_GPIOB_CLK_ENABLE();
+  __HAL_RCC_GPIOE_CLK_ENABLE();
+  __HAL_RCC_GPIOD_CLK_ENABLE();
+
+  /*Configure GPIO pin Output Level */
+  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_0, GPIO_PIN_RESET);
+
+  /*Configure GPIO pin Output Level */
+  HAL_GPIO_WritePin(GPIOE, GPIO_PIN_10, GPIO_PIN_RESET);
+
+  /*Configure GPIO pin Output Level */
+  HAL_GPIO_WritePin(GPIOD, GPIO_PIN_0, GPIO_PIN_RESET);
+
+  /*Configure GPIO pins : PF9 PF6 */
+  GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_6;
+  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);
+
+  /*Configure GPIO pin : PB0 */
+  GPIO_InitStruct.Pin = GPIO_PIN_0;
+  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
+  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
+
+  /*Configure GPIO pin : PE10 */
+  GPIO_InitStruct.Pin = GPIO_PIN_10;
+  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
+  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
+
+  /*Configure GPIO pin : PE11 */
+  GPIO_InitStruct.Pin = GPIO_PIN_11;
+  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);
+
+  /*Configure GPIO pin : PD0 */
+  GPIO_InitStruct.Pin = GPIO_PIN_0;
+  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+  GPIO_InitStruct.Pull = GPIO_NOPULL;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
+  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
+
+}
+
+//Delay 1us x n 
+void delay_us(uint32_t n) // Or n*72 clock cycles
+{
+
+  uint32_t i = 0U;
+  uint32_t j = 0U;
+
+  for(i = n; i > 0; --i)
+  {
+    for(j = 12; j > 0; --j)
+    {
+      asm("nop");
+    }
+  }
+}
+
+/*
+void cpu_sw_delay(uint32_t n)
+{
+  uint32_t i = 0U;
+  uint32_t j = 0U;
+
+  for(i = 0U; i < n; ++i)
+  {
+    for(j = 0U; j < 72; ++j) //72 CPU ticks per microsecond
+    {
+      asm("nop");
+    }
+  }
+}
+
+*/
+
+  //Measures a HIGH pulse
+  long pulse_in(GPIO_TypeDef* echo_port) 
+  {
+    unsigned long counter = 0;
+    //Sensor#0 echo port
+    if(echo_port == GPIOE) {
+      //Stall and wait for echo PE11 to go high.
+      while((echo_port->IDR & 0x0800) == 0) {} 
+      //Time the pulse. Start counting clock cycles until the echoPin goes low.
+      while((echo_port->IDR & 0x0800) == 1) {
+        ++counter;
+        asm("nop");
+      }
+    }
+    //Sensor#1 echo port
+    else if(echo_port == GPIOF) {    
+      //Stall and wait for echo PF6 to go high.
+      while((echo_port->IDR & 0x0040) == 0) {} 
+      while((echo_port->IDR & 0x0800) == 1) {
+        ++counter;
+        asm("nop");
+      }
+    }
+    //Sensor#2 echo port
+    else if(echo_port == GPIOA) {
+      //Stall and wait for echo PA13 to go high.
+      while((echo_port->IDR & 0x2000) == 0) {} 
+      while((echo_port->IDR & 0x0800) == 1) {
+        ++counter;
+        asm("nop");
+      }
+    }
+
+    //Every 72 clock cycles yields 1 microseconds 
+    return counter/72;
+  }
+
+
+  int get_sensor_dist(GPIO_TypeDef* trig_port, GPIO_TypeDef* echo_port, uint16_t trigger)
+  {
+    //Preparing the trigger pin.
+    HAL_GPIO_WritePin(trig_port, trigger, GPIO_PIN_RESET);    
+    delay_us(2);                                                
+    //10us sensor required initiation pulse on the trigger pin. 
+    HAL_GPIO_WritePin(trig_port, trigger, GPIO_PIN_SET);   
+    delay_us(10);                                                   
+    HAL_GPIO_WritePin(trig_port, trigger, GPIO_PIN_RESET);   
+    //pulse_in returns the sound wave travel time in microseconds
+    duration = pulse_in(echo_port);
+    distance = duration*.0133858/2;
+    inches = distance%12;
+    //Delay 50ms as per manufacture recomendation 
+    delay_us(50000); 
+    return inches;
+  }
+
+
+
+
+// Arduino example 
+/*
+const int trigPin = 9; 
+const int echoPin = 10;
+
+// defines variables
+long duration;
+int distance;
+int feet;
+int inches;
+
+void setup() {
+pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
+pinMode(echoPin, INPUT); // Sets the echoPin as an Input
+Serial.begin(9600); // Starts the serial communication
+}
+
+void loop() {
+// Clears the trigPin
+digitalWrite(trigPin, LOW);
+delayMicroseconds(2);
+// Sets the trigPin on HIGH state for 10 micro seconds
+digitalWrite(trigPin, HIGH);
+delayMicroseconds(10);
+digitalWrite(trigPin, LOW);
+// Reads the echoPin, returns the sound wave travel time in microseconds
+duration = pulseIn(echoPin, HIGH);
+// Calculating the distance
+distance= duration*.0133858/2;
+// Prints the distance on the Serial Monitor
+feet = distance/12;
+inches = distance%12;
+Serial.print("Distance: ");
+Serial.print(feet); 
+Serial.print(" ft ");
+Serial.print(inches);
+Serial.print(" in\n");
+delay(500);
+}*/