osd-contiki/platform/zoul/dev/servo.c
2016-08-24 14:27:41 +02:00

132 lines
4.5 KiB
C

/*
* Copyright (c) 2016, Zolertia - http://www.zolertia.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup zoul-servo
* @{
*
* \file
* Driver for a generic Servo driver
*
* \author
* Antonio Lignan <alinan@zolertia.com>
*/
/*---------------------------------------------------------------------------*/
#include "contiki.h"
#include "dev/pwm.h"
#include "dev/gpio.h"
#include "servo.h"
/*---------------------------------------------------------------------------*/
#define DEBUG 0
#if DEBUG
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
int
servo_position(uint16_t gptab, uint8_t port, uint8_t pin, uint16_t pos)
{
uint8_t gpt_num;
uint8_t gpt_ab;
uint32_t count = 0;
if((gptab < SERVO_CHANNEL_1) && (gptab > SERVO_CHANNEL_7)) {
PRINTF("Servo: invalid servo channel\n");
return SERVO_ERROR;
}
/* CC2538 has 4 ports (A-D) and up to 8 pins (0-7) */
if((port > GPIO_D_NUM) || (pin > 7)) {
PRINTF("Servo: Invalid pin/port settings\n");
return SERVO_ERROR;
}
if(pos > SERVO_MAX_DEGREES) {
PRINTF("Servo: invalid position (max %u)\n", SERVO_MAX_DEGREES);
return SERVO_ERROR;
}
count = (SERVO_MAX_VAL - SERVO_MIN_VAL) * pos;
count /= SERVO_MAX_DEGREES;
count += SERVO_MIN_VAL;
gpt_num = (uint8_t)(gptab >> 8);
gpt_ab = (uint8_t)(gptab & 0x00FF);
PRINTF("Servo: F%uHz GPTNUM %u GPTAB %u --> %uº (%lu)\n", SERVO_DEFAULT_FREQ,
gpt_num, gpt_ab,
pos, count);
/* Use count as argument instead of percentage */
if(pwm_enable(SERVO_DEFAULT_FREQ, 0, count, gpt_num,gpt_ab) != PWM_SUCCESS) {
PRINTF("Servo: failed to configure the pwm channel\n");
return SERVO_ERROR;
}
/* Start the PWM as soon as possible, keep the pulses to lock the servo in the
* given position
*/
if(pwm_start(gpt_num, gpt_ab, port, pin) != PWM_SUCCESS) {
PRINTF("Servo: failed to initialize the pwm channel\n");
return SERVO_ERROR;
}
return SERVO_SUCCESS;
}
/*---------------------------------------------------------------------------*/
int
servo_stop(uint16_t gptab, uint8_t port, uint8_t pin)
{
uint8_t gpt_num;
uint8_t gpt_ab;
if((gptab < SERVO_CHANNEL_1) && (gptab > SERVO_CHANNEL_7)) {
PRINTF("Servo: invalid servo channel\n");
return SERVO_ERROR;
}
/* CC2538 has 4 ports (A-D) and up to 8 pins (0-7) */
if((port > GPIO_D_NUM) || (pin > 7)) {
PRINTF("Servo: Invalid pin/port settings\n");
return SERVO_ERROR;
}
gpt_num = (uint8_t)((gptab & 0xFF00) >> 8);
gpt_ab = (uint8_t)(gptab & 0x00FF);
if(pwm_disable(gpt_num, gpt_ab, port, pin) != PWM_SUCCESS) {
PRINTF("Servo: unable to disable the pwm channel\n");
return SERVO_ERROR;
}
return SERVO_SUCCESS;
}
/*---------------------------------------------------------------------------*/
/** @} */