flight/pios/stm32f10x/pios_servo.c

   1 /**
   2  ******************************************************************************
   3  * @addtogroup PIOS PIOS Core hardware abstraction layer
   4  * @{
   5  * @addtogroup   PIOS_SERVO RC Servo Functions
   6  * @brief Code to do set RC servo output
   7  * @{
   8  *
   9  * @file       pios_servo.c
  10  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
  11  * @brief      RC Servo routines (STM32 dependent)
  12  * @see        The GNU Public License (GPL) Version 3
  13  *
  14  *****************************************************************************/
  15 /*
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 3 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful, but
  22  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  23  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  24  * for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License along
  27  * with this program; if not, write to the Free Software Foundation, Inc.,
  28  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  29  */
  30
  31 #include "pios.h"
  32
  33 #ifdef PIOS_INCLUDE_SERVO
  34
  35 #include "pios_servo_priv.h"
  36 #include "pios_tim_priv.h"
  37
  38 /* Private Function Prototypes */
  39
  40 static const struct pios_servo_cfg *servo_cfg;
  41
  42 // determine if the related timer will work in synchronous (or OneShot/OneShot125) One Pulse mode.
  43 static uint8_t pios_servo_bank_mode[PIOS_SERVO_BANKS] = { 0 };
  44 // used to skip updates when pulse length is higher than update cycle
  45 static uint16_t pios_servo_bank_next_update[PIOS_SERVO_BANKS] = { 0 };
  46 static uint16_t pios_servo_bank_max_pulse[PIOS_SERVO_BANKS] = { 0 };
  47 // timer associated to each bank
  48 static TIM_TypeDef *pios_servo_bank_timer[PIOS_SERVO_BANKS] = { 0 };
  49
  50 // index of bank used for each pin
  51 static uint8_t *pios_servo_pin_bank;
  52
  53 #define PIOS_SERVO_TIMER_CLOCK 1000000
  54 #define PIOS_SERVO_SAFE_MARGIN 50
  55 /**
  56  * Initialise Servos
  57  */
  58 int32_t PIOS_Servo_Init(const struct pios_servo_cfg *cfg)
  59 {
  60     uint32_t tim_id;
  61
  62     if (PIOS_TIM_InitChannels(&tim_id, cfg->channels, cfg->num_channels, NULL, 0)) {
  63         return -1;
  64     }
  65
  66     /* Store away the requested configuration */
  67     servo_cfg = cfg;
  68     pios_servo_pin_bank = pios_malloc(sizeof(uint8_t) * cfg->num_channels);
  69
  70     uint8_t bank = 0;
  71     /* Configure the channels to be in output compare mode */
  72     for (uint8_t i = 0; i < cfg->num_channels; i++) {
  73         const struct pios_tim_channel *chan = &servo_cfg->channels[i];
  74         bool new = true;
  75         /* See if any previous channels use that same timer */
  76         for (uint8_t j = 0; (j < i) && new; j++) {
  77             new &= chan->timer != servo_cfg->channels[j].timer;
  78         }
  79
  80         if (new) {
  81             PIOS_Assert(bank < PIOS_SERVO_BANKS);
  82             for (uint8_t j = i; j < servo_cfg->num_channels; j++) {
  83                 if (servo_cfg->channels[j].timer == chan->timer) {
  84                     pios_servo_pin_bank[j] = bank;
  85                 }
  86             }
  87             pios_servo_bank_timer[bank] = chan->timer;
  88
  89             PIOS_Assert(bank < PIOS_SERVO_BANKS);
  90
  91             for (uint8_t j = i; j < servo_cfg->num_channels; j++) {
  92                 if (servo_cfg->channels[j].timer == chan->timer) {
  93                     pios_servo_pin_bank[j] = bank;
  94                 }
  95             }
  96             pios_servo_bank_timer[bank] = chan->timer;
  97
  98             TIM_ARRPreloadConfig(chan->timer, ENABLE);
  99             TIM_CtrlPWMOutputs(chan->timer, ENABLE);
 100             TIM_Cmd(chan->timer, ENABLE);
 101
 102             bank++;
 103         }
 104
 105         /* Set up for output compare function */
 106         switch (chan->timer_chan) {
 107         case TIM_Channel_1:
 108             TIM_OC1Init(chan->timer, &cfg->tim_oc_init);
 109             TIM_OC1PreloadConfig(chan->timer, TIM_OCPreload_Enable);
 110             break;
 111         case TIM_Channel_2:
 112             TIM_OC2Init(chan->timer, &cfg->tim_oc_init);
 113             TIM_OC2PreloadConfig(chan->timer, TIM_OCPreload_Enable);
 114             break;
 115         case TIM_Channel_3:
 116             TIM_OC3Init(chan->timer, &cfg->tim_oc_init);
 117             TIM_OC3PreloadConfig(chan->timer, TIM_OCPreload_Enable);
 118             break;
 119         case TIM_Channel_4:
 120             TIM_OC4Init(chan->timer, &cfg->tim_oc_init);
 121             TIM_OC4PreloadConfig(chan->timer, TIM_OCPreload_Enable);
 122             break;
 123         }
 124     }
 125
 126     return 0;
 127 }
 128
 129 /**
 130  * Set the servo update rate (Max 500Hz)
 131  * \param[in] array of rates in Hz
 132  * \param[in] array of timer clocks in Hz
 133  * \param[in] maximum number of banks
 134  */
 135 void PIOS_Servo_SetHz(const uint16_t *speeds, const uint32_t *clock, uint8_t banks)
 136 {
 137     PIOS_Assert(banks <= PIOS_SERVO_BANKS);
 138     if (!servo_cfg) {
 139         return;
 140     }
 141
 142     TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure = servo_cfg->tim_base_init;
 143     TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
 144     TIM_TimeBaseStructure.TIM_CounterMode   = TIM_CounterMode_Up;
 145
 146     for (uint8_t i = 0; i < banks && i < PIOS_SERVO_BANKS; i++) {
 147         const TIM_TypeDef *timer = pios_servo_bank_timer[i];
 148         if (timer) {
 149             uint32_t new_clock = PIOS_SERVO_TIMER_CLOCK;
 150             if (clock[i]) {
 151                 new_clock = clock[i];
 152             }
 153             TIM_TimeBaseStructure.TIM_Prescaler = (PIOS_MASTER_CLOCK / new_clock) - 1;
 154             TIM_TimeBaseStructure.TIM_Period    = ((new_clock / speeds[i]) - 1);
 155
 156             TIM_TimeBaseInit((TIM_TypeDef *)timer, &TIM_TimeBaseStructure);
 157         }
 158     }
 159 }
 160
 161 /**
 162  * Set servo position
 163  * \param[in] Servo Servo number (0-7)
 164  * \param[in] Position Servo position in microseconds
 165  */
 166 void PIOS_Servo_Set(uint8_t servo, uint16_t position)
 167 {
 168     /* Make sure servo exists */
 169     if (!servo_cfg || servo >= servo_cfg->num_channels) {
 170         return;
 171     }
 172
 173
 174     /* Update the position */
 175     const struct pios_tim_channel *chan = &servo_cfg->channels[servo];
 176     uint16_t val    = position;
 177     uint16_t margin = chan->timer->ARR / 50; // Leave 2% of period as margin to prevent overlaps
 178     if (val > (chan->timer->ARR - margin)) {
 179         val = chan->timer->ARR - margin;
 180     }
 181
 182     uint8_t bank = pios_servo_pin_bank[servo];
 183     if (pios_servo_bank_max_pulse[bank] < val) {
 184         pios_servo_bank_max_pulse[bank] = val;
 185     }
 186     switch (chan->timer_chan) {
 187     case TIM_Channel_1:
 188         TIM_SetCompare1(chan->timer, val);
 189         break;
 190     case TIM_Channel_2:
 191         TIM_SetCompare2(chan->timer, val);
 192         break;
 193     case TIM_Channel_3:
 194         TIM_SetCompare3(chan->timer, val);
 195         break;
 196     case TIM_Channel_4:
 197         TIM_SetCompare4(chan->timer, val);
 198         break;
 199     }
 200 }
 201
 202 void PIOS_Servo_Update()
 203 {
 204     for (uint8_t i = 0; (i < PIOS_SERVO_BANKS); i++) {
 205         const TIM_TypeDef *timer = pios_servo_bank_timer[i];
 206         if (timer && pios_servo_bank_mode[i] == PIOS_SERVO_BANK_MODE_SINGLE_PULSE) {
 207             // a pulse to be generated is longer than cycle period. skip this update.
 208             if (TIM_GetCounter((TIM_TypeDef *)timer) > (uint32_t)(pios_servo_bank_next_update[i] + PIOS_SERVO_SAFE_MARGIN)) {
 209                 TIM_GenerateEvent((TIM_TypeDef *)timer, TIM_EventSource_Update);
 210                 pios_servo_bank_next_update[i] = pios_servo_bank_max_pulse[i];
 211             }
 212         }
 213         pios_servo_bank_max_pulse[i] = 0;
 214     }
 215     for (uint8_t i = 0; (i < servo_cfg->num_channels); i++) {
 216         uint8_t bank = pios_servo_pin_bank[i];
 217         uint8_t mode = pios_servo_bank_mode[bank];
 218         if (mode == PIOS_SERVO_BANK_MODE_SINGLE_PULSE) {
 219             /* Update the position */
 220             const struct pios_tim_channel *chan = &servo_cfg->channels[i];
 221
 222             switch (chan->timer_chan) {
 223             case TIM_Channel_1:
 224                 TIM_SetCompare1(chan->timer, 0);
 225                 break;
 226             case TIM_Channel_2:
 227                 TIM_SetCompare2(chan->timer, 0);
 228                 break;
 229             case TIM_Channel_3:
 230                 TIM_SetCompare3(chan->timer, 0);
 231                 break;
 232             case TIM_Channel_4:
 233                 TIM_SetCompare4(chan->timer, 0);
 234                 break;
 235             }
 236         }
 237     }
 238 }
 239
 240 void PIOS_Servo_SetBankMode(uint8_t bank, uint8_t mode)
 241 {
 242     PIOS_Assert(bank < PIOS_SERVO_BANKS);
 243     pios_servo_bank_mode[bank] = mode;
 244
 245     if (pios_servo_bank_timer[bank]) {
 246         for (uint8_t i = 0; (i < servo_cfg->num_channels); i++) {
 247             if (pios_servo_pin_bank[i] == bank) {
 248                 const struct pios_tim_channel *chan = &servo_cfg->channels[i];
 249                 /* Set up for output compare function */
 250                 switch (chan->timer_chan) {
 251                 case TIM_Channel_1:
 252                     TIM_OC1PolarityConfig(chan->timer, TIM_OCPolarity_High);
 253                     break;
 254                 case TIM_Channel_2:
 255                     TIM_OC2PolarityConfig(chan->timer, TIM_OCPolarity_High);
 256                     break;
 257                 case TIM_Channel_3:
 258                     TIM_OC3PolarityConfig(chan->timer, TIM_OCPolarity_High);
 259                     break;
 260                 case TIM_Channel_4:
 261                     TIM_OC4PolarityConfig(chan->timer, TIM_OCPolarity_High);
 262                     break;
 263                 }
 264             }
 265         }
 266
 267         // Setup the timer accordingly
 268         TIM_SelectOnePulseMode(pios_servo_bank_timer[bank], TIM_OPMode_Repetitive);
 269         TIM_Cmd(pios_servo_bank_timer[bank], ENABLE);
 270     }
 271 }
 272
 273
 274 uint8_t PIOS_Servo_GetPinBank(uint8_t pin)
 275 {
 276     if (pin < servo_cfg->num_channels) {
 277         return pios_servo_pin_bank[pin];
 278     } else {
 279         return 0;
 280     }
 281 }
 282
 283 #endif /* PIOS_INCLUDE_SERVO */