stmhal: Servo driver can move at a given speed.

stmhal/servo.c

@@ -2,6 +2,7 @@
 
 #include "stm32f4xx_hal.h"
 
+#include "nlr.h"
 #include "misc.h"
 #include "mpconfig.h"
 #include "qstr.h"
@@ -13,25 +14,85 @@
 // they are both 32-bit counters with 16-bit prescaler
 // we use TIM2
 
-STATIC TIM_HandleTypeDef servo_TimHandle;
+#define PYB_SERVO_NUM (4)
+
+typedef struct _pyb_servo_obj_t {
+    mp_obj_base_t base;
+    uint16_t servo_id;
+    uint16_t time_left;
+    int16_t pulse_accum;
+    uint16_t pulse_cur;
+    uint16_t pulse_dest;
+} pyb_servo_obj_t;
+
+STATIC const mp_obj_type_t servo_obj_type;
+
+STATIC pyb_servo_obj_t pyb_servo_obj[PYB_SERVO_NUM];
+
+TIM_HandleTypeDef servo_TIM2_Handle;
 
 void servo_init(void) {
     // TIM2 clock enable
     __TIM2_CLK_ENABLE();
 
+    // set up and enable interrupt
+    HAL_NVIC_SetPriority(TIM2_IRQn, 6, 0);
+    HAL_NVIC_EnableIRQ(TIM2_IRQn);
+
     // PWM clock configuration
-    servo_TimHandle.Instance = TIM2;
-    servo_TimHandle.Init.Period = 2000; // timer cycles at 50Hz
-    servo_TimHandle.Init.Prescaler = ((SystemCoreClock / 2) / 100000) - 1; // timer runs at 100kHz
-    servo_TimHandle.Init.ClockDivision = 0;
-    servo_TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
-    HAL_TIM_PWM_Init(&servo_TimHandle);
+    servo_TIM2_Handle.Instance = TIM2;
+    servo_TIM2_Handle.Init.Period = 2000; // timer cycles at 50Hz
+    servo_TIM2_Handle.Init.Prescaler = ((SystemCoreClock / 2) / 100000) - 1; // timer runs at 100kHz
+    servo_TIM2_Handle.Init.ClockDivision = 0;
+    servo_TIM2_Handle.Init.CounterMode = TIM_COUNTERMODE_UP;
+    HAL_TIM_PWM_Init(&servo_TIM2_Handle);
+
+    // reset servo objects
+    for (int i = 0; i < PYB_SERVO_NUM; i++) {
+        pyb_servo_obj[i].base.type = &servo_obj_type;
+        pyb_servo_obj[i].servo_id = i + 1;
+        pyb_servo_obj[i].time_left = 0;
+        pyb_servo_obj[i].pulse_cur = 150; // units of 10us
+        pyb_servo_obj[i].pulse_dest = 0;
+    }
+}
+
+#include "led.h"
+void servo_timer_irq_callback(void) {
+    led_toggle(1);
+    bool need_it = false;
+    for (int i = 0; i < PYB_SERVO_NUM; i++) {
+        pyb_servo_obj_t *s = &pyb_servo_obj[i];
+        if (s->pulse_cur != s->pulse_dest) {
+            if (s->time_left <= 1) {
+                s->pulse_cur = s->pulse_dest;
+                s->time_left = 0;
+            } else {
+                s->pulse_accum += s->pulse_dest - s->pulse_cur;
+                s->pulse_cur += s->pulse_accum / s->time_left;
+                s->pulse_accum %= s->time_left;
+                s->time_left--;
+                need_it = true;
+            }
+            switch (s->servo_id) {
+                case 1: TIM2->CCR1 = s->pulse_cur; break;
+                case 2: TIM2->CCR2 = s->pulse_cur; break;
+                case 3: TIM2->CCR3 = s->pulse_cur; break;
+                case 4: TIM2->CCR4 = s->pulse_cur; break;
+            }
+        }
+    }
+    if (need_it) {
+        __HAL_TIM_ENABLE_IT(&servo_TIM2_Handle, TIM_IT_UPDATE);
+    } else {
+        __HAL_TIM_DISABLE_IT(&servo_TIM2_Handle, TIM_IT_UPDATE);
+    }
 }
 
-STATIC void servo_init_channel(int channel_in) {
+STATIC void servo_init_channel(pyb_servo_obj_t *s) {
     uint32_t pin;
     uint32_t channel;
-    switch (channel_in) {
+    switch (s->servo_id) {
         case 1: pin = GPIO_PIN_0; channel = TIM_CHANNEL_1; break;
         case 2: pin = GPIO_PIN_1; channel = TIM_CHANNEL_2; break;
         case 3: pin = GPIO_PIN_2; channel = TIM_CHANNEL_3; break;
@@ -51,13 +112,13 @@ STATIC void servo_init_channel(int channel_in) {
     // PWM mode configuration
     TIM_OC_InitTypeDef oc_init;
     oc_init.OCMode = TIM_OCMODE_PWM1;
-    oc_init.Pulse = 150; // units of 10us
+    oc_init.Pulse = s->pulse_cur; // units of 10us
     oc_init.OCPolarity = TIM_OCPOLARITY_HIGH;
     oc_init.OCFastMode = TIM_OCFAST_DISABLE;
-    HAL_TIM_PWM_ConfigChannel(&servo_TimHandle, &oc_init, channel);
+    HAL_TIM_PWM_ConfigChannel(&servo_TIM2_Handle, &oc_init, channel);
 
     // start PWM
-    HAL_TIM_PWM_Start(&servo_TimHandle, channel);
+    HAL_TIM_PWM_Start(&servo_TIM2_Handle, channel);
 }
 
 /******************************************************************************/
@@ -89,35 +150,39 @@ STATIC mp_obj_t pyb_pwm_set(mp_obj_t period, mp_obj_t pulse) {
 
 MP_DEFINE_CONST_FUN_OBJ_2(pyb_pwm_set_obj, pyb_pwm_set);
 
-typedef struct _pyb_servo_obj_t {
-    mp_obj_base_t base;
-    uint servo_id;
-} pyb_servo_obj_t;
-
 STATIC void servo_obj_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
     pyb_servo_obj_t *self = self_in;
-    print(env, "<Servo %lu>", self->servo_id);
+    print(env, "<Servo %lu at %lu>", self->servo_id, self->pulse_cur);
 }
 
-STATIC mp_obj_t servo_obj_angle(mp_obj_t self_in, mp_obj_t angle) {
-    pyb_servo_obj_t *self = self_in;
+STATIC mp_obj_t servo_obj_angle(uint n_args, const mp_obj_t *args) {
+    pyb_servo_obj_t *self = args[0];
+    if (n_args == 1) {
+        // get angle
+        return mp_obj_new_int((self->pulse_cur - 152) * 90 / 85);
+    } else {
 #if MICROPY_ENABLE_FLOAT
-    machine_int_t v = 152 + 85.0 * mp_obj_get_float(angle) / 90.0;
+        machine_int_t v = 152 + 85.0 * mp_obj_get_float(args[1]) / 90.0;
 #else
-    machine_int_t v = 152 + 85 * mp_obj_get_int(angle) / 90;
+        machine_int_t v = 152 + 85 * mp_obj_get_int(args[1]) / 90;
 #endif
-    if (v < 65) { v = 65; }
-    if (v > 210) { v = 210; }
-    switch (self->servo_id) {
-        case 1: TIM2->CCR1 = v; break;
-        case 2: TIM2->CCR2 = v; break;
-        case 3: TIM2->CCR3 = v; break;
-        case 4: TIM2->CCR4 = v; break;
+        if (v < 65) { v = 65; }
+        if (v > 210) { v = 210; }
+        self->pulse_dest = v;
+        if (n_args == 2) {
+            // set angle immediately
+            self->time_left = 0;
+        } else {
+            // set angle over a given time (given in milli seconds)
+            self->time_left = mp_obj_get_int(args[2]) / 20;
+            self->pulse_accum = 0;
+        }
+        servo_timer_irq_callback();
+        return mp_const_none;
     }
-    return mp_const_none;
 }
 
-STATIC MP_DEFINE_CONST_FUN_OBJ_2(servo_obj_angle_obj, servo_obj_angle);
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(servo_obj_angle_obj, 1, 3, servo_obj_angle);
 
 STATIC const mp_method_t servo_methods[] = {
     { "angle", &servo_obj_angle_obj },
@@ -131,12 +196,17 @@ STATIC const mp_obj_type_t servo_obj_type = {
     .methods = servo_methods,
 };
 
-STATIC mp_obj_t pyb_Servo(mp_obj_t servo_id) {
-    pyb_servo_obj_t *o = m_new_obj(pyb_servo_obj_t);
-    o->base.type = &servo_obj_type;
-    o->servo_id = mp_obj_get_int(servo_id);
-    servo_init_channel(o->servo_id);
-    return o;
+STATIC mp_obj_t pyb_Servo(mp_obj_t servo_id_o) {
+    machine_int_t servo_id = mp_obj_get_int(servo_id_o) - 1;
+    if (0 <= servo_id && servo_id < PYB_SERVO_NUM) {
+        pyb_servo_obj_t *s = &pyb_servo_obj[servo_id];
+        s->pulse_dest = s->pulse_cur;
+        s->time_left = 0;
+        servo_init_channel(s);
+        return s;
+    } else {
+        nlr_jump(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Servo %d does not exist", servo_id));
+    }
 }
 
 MP_DEFINE_CONST_FUN_OBJ_1(pyb_Servo_obj, pyb_Servo);

stmhal/servo.h

+extern TIM_HandleTypeDef servo_TIM2_Handle;
+
 void servo_init(void);
+void servo_timer_irq_callback(void);
 
 MP_DECLARE_CONST_FUN_OBJ(pyb_servo_set_obj);
 MP_DECLARE_CONST_FUN_OBJ(pyb_pwm_set_obj);

stmhal/stm32f4xx_hal_msp.c

@@ -50,6 +50,12 @@
 #include "usbd_cdc_msc.h"
 #include "usbd_cdc_interface.h"
 
+#include "misc.h"
+#include "mpconfig.h"
+#include "qstr.h"
+#include "obj.h"
+#include "servo.h"
+
 /** @addtogroup STM32F4xx_HAL_Driver
   * @{
   */
@@ -155,6 +161,14 @@ void HAL_RTC_MspDeInit(RTC_HandleTypeDef *hrtc)
    __HAL_RCC_RTC_DISABLE();
 }
 
+void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim) {
+    if (htim == &USBD_CDC_TIM3_Handle) {
+        USBD_CDC_HAL_TIM_PeriodElapsedCallback();
+    } else if (htim == &servo_TIM2_Handle) {
+        servo_timer_irq_callback();
+    }
+}
+
 /**
   * @}
   */

stmhal/stm32f4xx_it.c

@@ -42,12 +42,15 @@
 
 #include "stm32f4xx_it.h"
 #include "stm32f4xx_hal.h"
+#include "usbd_cdc_msc.h"
+#include "usbd_cdc_interface.h"
 
 #include "misc.h"
 #include "mpconfig.h"
 #include "qstr.h"
 #include "obj.h"
 #include "exti.h"
+#include "servo.h"
 
 /** @addtogroup STM32F4xx_HAL_Examples
   * @{
@@ -64,7 +67,6 @@
 
 extern void fatality();
 extern PCD_HandleTypeDef hpcd;
-extern TIM_HandleTypeDef USBD_CDC_TimHandle;
 
 /* Private function prototypes -----------------------------------------------*/
 /* Private functions ---------------------------------------------------------*/
@@ -349,9 +351,14 @@ void RTC_WKUP_IRQHandler(void) {
     Handle_EXTI_Irq(EXTI_RTC_WAKEUP);
 }
 
+void TIM2_IRQHandler(void) {
+    // servo timer is TIM2
+    HAL_TIM_IRQHandler(&servo_TIM2_Handle);
+}
+
 void TIM3_IRQHandler(void) {
     // USBD CDC timer is TIM3
-    HAL_TIM_IRQHandler(&USBD_CDC_TimHandle);
+    HAL_TIM_IRQHandler(&USBD_CDC_TIM3_Handle);
 }
 
 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

stmhal/usbd_cdc_interface.c

@@ -66,7 +66,7 @@ static int user_interrupt_char = VCP_CHAR_NONE;
 static void *user_interrupt_data = NULL;
 
 /* TIM handler declaration */
-TIM_HandleTypeDef USBD_CDC_TimHandle;
+TIM_HandleTypeDef USBD_CDC_TIM3_Handle;
 /* USB handler declaration */
 extern USBD_HandleTypeDef hUSBDDevice;
 
@@ -132,7 +132,7 @@ static int8_t CDC_Itf_Init(void)
   
   /*##-4- Start the TIM Base generation in interrupt mode ####################*/
   /* Start Channel1 */
-  if(HAL_TIM_Base_Start_IT(&USBD_CDC_TimHandle) != HAL_OK)
+  if(HAL_TIM_Base_Start_IT(&USBD_CDC_TIM3_Handle) != HAL_OK)
   {
     /* Starting Error */
   }
@@ -250,8 +250,7 @@ static int8_t CDC_Itf_Control(uint8_t cmd, uint8_t* pbuf, uint16_t length) {
   * @param  htim: TIM handle
   * @retval None
   */
-void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
-{
+void USBD_CDC_HAL_TIM_PeriodElapsedCallback(void) {
   uint32_t buffptr;
   uint32_t buffsize;
   
@@ -388,7 +387,7 @@ int USBD_CDC_RxGet(void) {
 static void TIM_Config(void)
 {  
   /* Set TIMx instance */
-  USBD_CDC_TimHandle.Instance = USBD_CDC_TIMx;
+  USBD_CDC_TIM3_Handle.Instance = USBD_CDC_TIMx;
   
   /* Initialize TIM3 peripheral as follow:
        + Period = 10000 - 1
@@ -396,11 +395,11 @@ static void TIM_Config(void)
        + ClockDivision = 0
        + Counter direction = Up
   */
-  USBD_CDC_TimHandle.Init.Period = (USBD_CDC_POLLING_INTERVAL*1000) - 1;
-  USBD_CDC_TimHandle.Init.Prescaler = 84-1;
-  USBD_CDC_TimHandle.Init.ClockDivision = 0;
-  USBD_CDC_TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
-  if(HAL_TIM_Base_Init(&USBD_CDC_TimHandle) != HAL_OK)
+  USBD_CDC_TIM3_Handle.Init.Period = (USBD_CDC_POLLING_INTERVAL*1000) - 1;
+  USBD_CDC_TIM3_Handle.Init.Prescaler = 84-1;
+  USBD_CDC_TIM3_Handle.Init.ClockDivision = 0;
+  USBD_CDC_TIM3_Handle.Init.CounterMode = TIM_COUNTERMODE_UP;
+  if(HAL_TIM_Base_Init(&USBD_CDC_TIM3_Handle) != HAL_OK)
   {
     /* Initialization Error */
   }

stmhal/usbd_cdc_interface.h

@@ -36,8 +36,8 @@
 /* Definition for TIMx clock resources */
 #define USBD_CDC_TIMx                             TIM3
 #define USBD_CDC_TIMx_CLK_ENABLE                  __TIM3_CLK_ENABLE
-#define USBD_CDC_TIMx_FORCE_RESET()               __USART3_FORCE_RESET()
-#define USBD_CDC_TIMx_RELEASE_RESET()             __USART3_RELEASE_RESET()
+#define USBD_CDC_TIMx_FORCE_RESET()               __TIM3_FORCE_RESET()
+#define USBD_CDC_TIMx_RELEASE_RESET()             __TIM3_RELEASE_RESET()
 
 /* Definition for TIMx's NVIC */
 #define USBD_CDC_TIMx_IRQn                        TIM3_IRQn
@@ -47,8 +47,11 @@
    The period depends on USBD_CDC_POLLING_INTERVAL */
 #define USBD_CDC_POLLING_INTERVAL             10 /* in ms. The max is 65 and the min is 1 */
 
+extern TIM_HandleTypeDef USBD_CDC_TIM3_Handle;
 extern const USBD_CDC_ItfTypeDef USBD_CDC_fops;
 
+void USBD_CDC_HAL_TIM_PeriodElapsedCallback(void);
+
 int USBD_CDC_IsConnected(void);
 void USBD_CDC_SetInterrupt(int chr, void *data);
 void USBD_CDC_Tx(const char *str, uint32_t len);