/****************************************************************************
*
* Copyright (c) 2006 Dave Hylands <dhylands@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*
****************************************************************************/
/**
*
* @file Switch.h
*
* @brief Provides an API for talking to character style LCDs. These
* functions are designed around the HD44780 based LCD Controllers.
*
****************************************************************************/
#if !defined( SWITCH_H )
#define SWITCH_H /**< Include Guard */
/* ---- Include Files ---------------------------------------------------- */
#include <stdint.h>
#include "Config.h"
/* ---- Constants and Types ---------------------------------------------- */
// This file expects the following options to be defined in Config.h
//
// CFG_NUM_SWITCHES - Determines the total number of switches that
// will be checked.
//
// CFG_SWITCH_BOUNCE_ON_COUNT - Determines the number of times that the
// the swith needs to be seen on before it's
// considered to be really on.
//
// CFG_SWITCH_BOUNCE_OFF_COUNT - Determines the number of times that the
// the swith needs to be seen off before it's
// considered to be really off.
//
// The caller is responsible for setting up the raw switch states and
// calling CheckSwitches on some type of periodic basis - assumed to be once
// every 10 msec, but this is pretty arbitrary.
#if !defined( CFG_NUM_SWITCHES )
# error CFG_NUM_SWITCHES not defined
#endif
#if !defined( CFG_SWITCH_BOUNCE_ON_COUNT )
# define CFG_SWITCH_BOUNCE_ON_COUNT 3
#endif
#if !defined( CFG_SWITCH_BOUNCE_OFF_COUNT )
# define CFG_SWITCH_BOUNCE_OFF_COUNT CFG_SWITCH_BOUNCE_ON_COUNT
#endif
#if defined( AVR )
typedef uint8_t SwitchEvent_t;
typedef uint8_t SwitchNum_t;
typedef uint8_t SwitchBool_t;
#else
typedef unsigned SwitchEvent_t;
typedef unsigned SwitchNum_t;
typedef unsigned SwitchBool_t;
#endif
typedef uint8_t SwitchCount_t;
typedef uint8_t SwitchState_t;
#define SWITCH_EVENT_RELEASED 0
#define SWITCH_EVENT_PRESSED 1
/* ---- Variable Externs ------------------------------------------------- */
#define NUM_SWITCH_BYTES (( CFG_NUM_SWITCHES + 7 ) / 8 )
extern uint8_t gSwitchRaw[ NUM_SWITCH_BYTES ];
extern uint8_t gSwitchEnabled[ NUM_SWITCH_BYTES ];
#define SWITCH_RAW_BYTE( sw ) (gSwitchRaw[ (sw) / 8 ])
#define SWITCH_ENABLED_BYTE( sw ) (gSwitchEnabled[ (sw) / 8 ])
#define SWITCH_MASK( sw ) ( 1 << ( sw & 7 ))
/* ---- Inline Functions ------------------------------------------------- */
/***************************************************************************/
/**
* Checks to see if a switch is pressed. This is a raw check and doesn't
* factor debouncing into the equation
*/
static inline SwitchBool_t IsRawSwitchPressed( SwitchNum_t sw )
{
return ( SWITCH_RAW_BYTE( sw ) & SWITCH_MASK( sw )) != 0;
} // IsRawSwitchPressed
/***************************************************************************/
/**
* Checks to see if a switch is enabled.
*/
static inline SwitchBool_t IsSwitchEnabled( SwitchNum_t sw )
{
return ( SWITCH_ENABLED_BYTE( sw ) & SWITCH_MASK( sw )) != 0;
} // IsSwitchEnabled
/***************************************************************************/
/**
* Sets an individual switch as being set or cleared.
*/
static inline void SetRawSwitch( SwitchNum_t sw, SwitchBool_t isSet )
{
if ( isSet )
{
SWITCH_RAW_BYTE( sw ) |= SWITCH_MASK( sw );
}
else
{
SWITCH_RAW_BYTE( sw ) &= ~SWITCH_MASK( sw );
}
} // SetRawSwitch
/***************************************************************************/
/**
* Enables a switch for processing.
*/
static inline void EnableSwitch( SwitchNum_t sw )
{
SWITCH_ENABLED_BYTE( sw ) |= SWITCH_MASK( sw );
} // EnableSwitch
/***************************************************************************/
/**
* Disables a switch for processing.
*/
static inline void DisableSwitch( SwitchNum_t sw )
{
SWITCH_ENABLED_BYTE( sw ) &= ~SWITCH_MASK( sw );
} // EnableSwitch
/* ---- Function Prototypes ---------------------------------------------- */
void CheckSwitches( void );
// The caller is expected to provide the SwitchEvent fnuction with the
// following prototype.
void SwitchEvent( SwitchNum_t switchNum, SwitchEvent_t event );
#endif // SWITCH_H
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