gobot.io/x/gobot/v2@v2.1.0/platforms/digispark/littleWire_servo.c (about)

     1  /*
     2  	Higher level servo driving library for Little Wire.
     3  
     4  	Copyright (C) <2013> ihsan Kehribar <ihsan@kehribar.me>
     5  	
     6  	Permission is hereby granted, free of charge, to any person obtaining a copy of
     7  	this software and associated documentation files (the "Software"), to deal in
     8  	the Software without restriction, including without limitation the rights to
     9  	use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
    10  	of the Software, and to permit persons to whom the Software is furnished to do
    11  	so, subject to the following conditions:
    12  
    13  	The above copyright notice and this permission notice shall be included in all
    14  	copies or substantial portions of the Software.
    15  
    16  	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    17  	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    18  	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    19  	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    20  	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    21  	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    22  	SOFTWARE.
    23  */
    24  
    25  #include "littleWire_servo.h"
    26  
    27  /********************************************************************************
    28  * Useful definitions
    29  ********************************************************************************/
    30  const float MIN_LIMIT = 0.45; // in miliseconds
    31  const float MAX_LIMIT = 2.45; // in miliseconds
    32  const float STEP_SIZE = 0.062; // in miliseconds
    33  const float RANGE = 180.0; // in degrees
    34  /*******************************************************************************/
    35  
    36  /********************************************************************************
    37  * Servo module initialization
    38  ********************************************************************************/
    39  void servo_init(littleWire* lwHandle)
    40  {
    41  	pwm_init(lwHandle); // Initialize the PWM hardware.
    42  	pinMode(lwHandle,PWMA,OUTPUT); pinMode(lwHandle,PWMB,OUTPUT); // Set PWM pins output.
    43  	pwm_updatePrescaler(lwHandle,1024); // Make sure the PWM prescaler is set correctly.
    44  }
    45  /*******************************************************************************/
    46  
    47  /********************************************************************************
    48  * Servo locations update
    49  *	locationChannelA in degrees
    50  *	locationChannelB in degrees
    51  ********************************************************************************/
    52  void servo_updateLocation(littleWire* lwHandle,unsigned char locationChannelA,unsigned char locationChannelB)
    53  {
    54  	locationChannelA=(((locationChannelA/RANGE)*(MAX_LIMIT-MIN_LIMIT))+MIN_LIMIT)/STEP_SIZE;
    55  	locationChannelB=(((locationChannelB/RANGE)*(MAX_LIMIT-MIN_LIMIT))+MIN_LIMIT)/STEP_SIZE;
    56  	pwm_updateCompare(lwHandle,locationChannelA,locationChannelB);
    57  }
    58  /*******************************************************************************/