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/*! \file servo.h \brief Interrupt-driven RC Servo function library. */
//*****************************************************************************
//
// File Name : 'servo.h'
// Title : Interrupt-driven RC Servo function library
// Author : Pascal Stang - Copyright (C) 2002
// Created : 7/31/2002
// Revised : 8/02/2002
// Version : 1.0
// Target MCU : Atmel AVR Series
// Editor Tabs : 4
//
/// \ingroup driver_sw
/// \defgroup servo Interrupt-driven RC Servo Function Library (servo.c)
/// \code #include "servo.h" \endcode
/// \par Overview
/// This code allows you to drive up to 8 RC servos from any
/// combination of ports and pins on the AVR processor. Using interrupts,
/// this code continuously sends control signals to the servo to maintain
/// position even while your code is doing other work.
///
/// The servoInit and servoOff effectively turn on and turn off servo
/// control. When you run ServoInit, it automatically assigns each
/// "channel" of servo control to be output on the SERVO_DEFAULT_PORT.
/// One "channel" of servo control can control one servo and must be
/// assigned single I/O pin for output.
///
/// If you're using all eight channels (SERVO_NUM_CHANNELS = 8), then
/// then by default the code will use SERVO_DEFAULT_PORT pins 0-7.
/// If you're only using four channels, then pins 0-3 will be used by
/// default.
///
/// The command servoSetChannelIO(channel, port, pin) allows you to
/// reassign the output of any channel to any port and I/O pin you
/// choose. For exampe, if you have an RC servo connected to PORTC, pin 6,
/// and you wish to use channel 2 to control it, use:
///
/// servoSerChannelIO( 2, _SFR_IO_ADDR(PORTC), 6)
///
/// (NOTE: you must include the "_SRF_IO_ADDR()" part around your port)
///
/// The servoSetPostion and servoGetPosition commands allow you to command
/// a given servo to your desired position. The position you request must
/// lie between the SERVO_MIN and SERVO_MAX limit you defined.
///
/// \WARNING: This servo library has been tested to work without issue on
/// several different AVR processors and with several different brands/kinds
/// of servos. However:
/// - Proper output duty cylces are dependent upon a user calibation and
/// configuration.
/// - IF YOUR SERVOS ARE EXCEPTIONALLY POWERFUL, AN ERRONEOUS OUTPUT DUTY
/// CYCLE GENERATED FROM THIS CODE OR ANY OTHER SOURCE CAN DAMAGE YOUR
/// SERVO'S INTERNAL DRIVER CHIP OR ITS GEARS!
/// - I have never experienced any servo damage from erroneous control signal
/// input, but it is possible.
//
// This code is distributed under the GNU Public License
// which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************
#ifndef SERVO_H
#define SERVO_H
#include "global.h"
#include "timer.h"
// include configuration
#include "servoconf.h"
typedef struct struct_ServoChannel
{
// hardware I/O port and pin for this channel
uint8_t port;
uint8_t pin;
// PWM duty setting which corresponds to servo position
uint16_t duty;
} ServoChannelType;
// functions
// initializes servo system
// You must run this to begin servo control
void servoInit(void);
// turns off servo system
// This stops controlling the servos and
// returns control of the SERVOPORT to your code
void servoOff(void);
// set the port and I/O pin you wish to use for a given channel
// If you do not assign a port and I/O pin for a channel (ie. you don't
// use this command) then all output will be done through the
// SERVO_DEFAULT_PORT. See above definition of SERVO_DEFAULT_PORT.
void servoSetChannelIO(uint8_t channel, uint8_t port, uint8_t pin);
// set and get servo position on a given channel
// servoSetPosition() commands the servo on <channel> to the position you
// desire. The position input must lie between 0 and POSITION_MAX and
// will be automatically scaled to raw positions between SERVO_MIN and
// SERVO_MAX
// servoGetPosition() returns the most recently set postition of the
// servo on <channel>. The return value will be scaled 0->POSITION_MAX
void servoSetPosition(uint8_t channel, uint8_t position);
uint8_t servoGetPosition(uint8_t channel);
// set and get raw servo position on a given channel
// Works like non-raw commands but position is not scaled. Position must
// be between SERVO_MIN and SERVO_MAX
void servoSetPositionRaw(uint8_t channel, uint16_t position);
uint16_t servoGetPositionRaw(uint8_t channel);
// servo interrupt service routine
void servoService(void);
#endif
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