ADD: ppm input

Inc/config.h

@@ -10,12 +10,15 @@
 #define MILLI_PSI (PSI * 1000)
 #define MILLI_V (V * 1000)
 
-#define PWM_FREQ       16000     // PWM frequency in Hz
-#define DEAD_TIME      32        // PWM deadtime
+#define PWM_FREQ         16000     // PWM frequency in Hz
+#define DEAD_TIME        32        // PWM deadtime
 
-#define DC_CUR_LIMIT   5         // Motor DC current limit in amps
+#define DC_CUR_LIMIT     5         // Motor DC current limit in amps
 
 #define DEBUG_SERIAL_SERVOTERM
 //#define DEBUG_SERIAL_ASCII
-#define DEBUG_BAUD     115200    // UART baud rate
+#define DEBUG_BAUD       115200    // UART baud rate
 //#define DEBUG_I2C_LCD
+
+#define CONTROL_PPM                // use PPM CONTROL_PPM
+#define PPM_NUM_CHANNELS 6         // number of PPM channels to receive

Inc/defines.h

@@ -117,6 +117,8 @@
 #define CHARGER_PIN GPIO_PIN_12
 #define CHARGER_PORT GPIOA
 
+#define DELAY_TIM_FREQUENCY_US 1000000
+
 #define MOTOR_AMP_CONV_DC_AMP 0.02
 #define ADC_BATTERY_VOLT      0.02647435897435897435897435897436
 

Makefile

@@ -35,10 +35,11 @@ Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_adc.c \
 Drivers/STM32F1xx_HAL_Driver/Src/stm32f1xx_hal_uart.c \
 Src/system_stm32f1xx.c \
 Src/setup.c \
-Src/stm32f1xx_it.c \
+Src/control.c \
 Src/main.c \
 Src/bldc.c \
 Src/comms.c \
+Src/stm32f1xx_it.c \
 
 # ASM sources
 ASM_SOURCES =  \

Src/control.c

@@ -0,0 +1,52 @@
+
+#include "stm32f1xx_hal.h"
+#include "defines.h"
+#include "setup.h"
+#include "config.h"
+
+TIM_HandleTypeDef TimHandle;
+uint16_t ppm_captured_value[PPM_NUM_CHANNELS+1] = {0};
+uint8_t ppm_count = 0;
+uint32_t timeout = 0;
+
+void PPM_ISR_Callback() {
+  // Dummy loop with 16 bit count wrap around
+  uint16_t rc_delay = TIM2->CNT;
+  TIM2->CNT = 0;
+
+  HAL_TIM_Base_Stop(&TimHandle);
+  __HAL_RCC_TIM2_CLK_DISABLE();
+
+  if (rc_delay > 3000) {
+    ppm_count = 0;
+  }
+  else if (ppm_count < PPM_NUM_CHANNELS){
+    timeout = 0;
+    ppm_captured_value[ppm_count] = CLAMP(rc_delay, 1000, 2000) - 1000;
+    ppm_count++;
+  }
+  __HAL_RCC_TIM2_CLK_ENABLE();
+  HAL_TIM_Base_Start(&TimHandle);
+}
+
+void PPM_Init() {
+  GPIO_InitTypeDef GPIO_InitStruct;
+  /*Configure GPIO pin : PA3 */
+  GPIO_InitStruct.Pin = GPIO_PIN_3;
+  GPIO_InitStruct.Mode = GPIO_MODE_IT_FALLING;
+  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
+  GPIO_InitStruct.Pull = GPIO_PULLDOWN;
+  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
+
+  __HAL_RCC_TIM2_CLK_ENABLE();
+  TimHandle.Instance = TIM2;
+  TimHandle.Init.Period = UINT16_MAX;
+  TimHandle.Init.Prescaler = (SystemCoreClock/DELAY_TIM_FREQUENCY_US)-1;;
+  TimHandle.Init.ClockDivision = 0;
+  TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
+  HAL_TIM_Base_Init(&TimHandle);
+
+  /* EXTI interrupt init*/
+  HAL_NVIC_SetPriority(EXTI3_IRQn, 0, 0);
+  HAL_NVIC_EnableIRQ(EXTI3_IRQn);
+}

Src/main.c

@@ -30,6 +30,7 @@ extern TIM_HandleTypeDef htim_right;
 extern ADC_HandleTypeDef hadc1;
 extern ADC_HandleTypeDef hadc2;
 extern volatile adc_buf_t adc_buffer;
+extern volatile uint16_t ppm_captured_value[PPM_NUM_CHANNELS+1];
 
 extern volatile int pwml;
 extern volatile int pwmr;
@@ -66,11 +67,18 @@ int main(void) {
   MX_ADC2_Init();
   UART_Init();
 
+  #ifdef CONTROL_PPM
+    PPM_Init();
+  #endif
+
   HAL_GPIO_WritePin(OFF_PORT, OFF_PIN, 1);
 
   HAL_ADC_Start(&hadc1);
   HAL_ADC_Start(&hadc2);
 
+  int lastSpeedL = 0, lastSpeedR = 0;
+  int speedL = 0, speedR = 0;
+
   while(1) {
     HAL_Delay(0);
     // int milli_cur = 3000;
@@ -83,8 +91,18 @@ int main(void) {
     // milli_vel_error_sum = CLAMP(milli_vel_error_sum, -200000, 200000);
     // pwm = CLAMP(milli_vel_cmd / 5 + milli_vel_error_sum / 200, -500, 500);
     // cmdl = 70;
-    pwml = 150;
-    pwmr = 150;
+
+    #ifdef CONTROL_PPM
+      speedR = -(CLAMP((((ppm_captured_value[1]-500)-(ppm_captured_value[0]-500)/2.0)*(ppm_captured_value[2]/500.0)), -800, 800));
+      speedL = -(CLAMP((((ppm_captured_value[1]-500)+(ppm_captured_value[0]-500)/2.0)*(ppm_captured_value[2]/500.0)), -800, 800));
+    #endif
+
+    if ((speedL < lastSpeedL + 50 && speedL > lastSpeedL - 50) && (speedR < lastSpeedR + 50 && speedR > lastSpeedR - 50)) {
+      pwmr = speedR;
+      pwml = speedL;
+    }
+    lastSpeedL = speedL;
+    lastSpeedR = speedR;
 
     // if(vel > milli_vel_cmd){
     //   HAL_GPIO_WritePin(LED_PORT, LED_PIN, 1);

Src/stm32f1xx_it.c

@@ -164,6 +164,13 @@ void SysTick_Handler(void) {
   /* USER CODE END SysTick_IRQn 1 */
 }
 
+
+void EXTI3_IRQHandler(void)
+{
+    PPM_ISR_Callback();
+    __HAL_GPIO_EXTI_CLEAR_IT(GPIO_PIN_3);
+}
+
 /******************************************************************************/
 /* STM32F1xx Peripheral Interrupt Handlers                                    */
 /* Add here the Interrupt Handlers for the used peripherals.                  */