www.pudn.com > Bit1611_demo_code.rar > KEY.C
/* **********************************************************************
Copyright (c) 2002-2006 Beyond Innovation Technology Co., Ltd
All rights are reserved. Reproduction in whole or in parts is
prohibited without the prior written consent of the copyright owner.
----------------------------------------------------------------------
Module: KEY.C - Keypad.
Purpose: Implementation of KEY module.
Version: 0.01 11:35AM 2005/11/17
Compiler: Keil 8051 C Compiler v8.01
Reference:
----------------------------------------------------------------------
Modification:
R0.01 11:35AM 2005/11/17 Jeffrey Chang
Reason:
1. Original.
Solution:
********************************************************************** */
#define _KEY_C_
/* ------------------------------------
Header Files
------------------------------------ */
#include "key.h"
/* ::::::::::::::::::::::::::::::::::::
Key scanning states
:::::::::::::::::::::::::::::::::::: */
#define KEY_STATE_UP 1
#define KEY_STATE_DEBOUNCE 2
#define KEY_STATE_REPEAT_START_DELAY 3
#define KEY_STATE_REPEAT_DELAY 4
#define NO_RELEASE_AFTER_STILL ON
/* ------------------------------------
Macro Definitions
------------------------------------ */
/* ------------------------------------
Type Definitions
------------------------------------ */
/* ------------------------------------
Variables Definitions
------------------------------------ */
static UB8 abKeyBfr[ KEY_BFR_SIZE ]; /* Keypad buffer */
/* Buffer index where next scan code will be inserted */
static UB8 bKeyBfrInIdx;
/* Buffer index where next scan code will be removed */
static UB8 bKeyBfrOutIdx;
#if (NO_RELEASE_AFTER_STILL)
// To filter out the RELEASE key after STILL one.
static BOOL fKeyNO_STILL;
#endif
/* ------------------------------------
Function Prototypes
------------------------------------ */
/* -------------------------------------------------------------------
Name: KEY_BufferFlush -
Purpose: To flush the key buffer data structure.
Passed: None.
Returns: None.
Notes:
------------------------------------------------------------------- */
void KEY_BufferFlush (void)
{
bKeyCnt = 0;
bKeyBfrInIdx = 0;
bKeyBfrOutIdx = 0;
} /* KEY_BufferFlush */
/* -------------------------------------------------------------------
Name: KEY_BufferIn -
Purpose: To insert a scan code into the key buffer data structure.
Passed:
UB8 bCode = a scan code.
Returns: None.
Notes:
1) THIS ONE MIGHT BE CALLED FROM different ISRs / Code.
Therefore no local variables are allowed otherwise it causes
a overlay error in Keil-C.
------------------------------------------------------------------- */
void KEY_BufferIn (UB8 bCode)
{
if (bCode)
{
if (bKeyCnt < KEY_BFR_SIZE)
{
bKeyCnt++;
abKeyBfr[ bKeyBfrInIdx++ ] = bCode;
if (bKeyBfrInIdx >= KEY_BFR_SIZE)
bKeyBfrInIdx = 0;
} /* if */
}
} /* KEY_BufferIn */
/* -------------------------------------------------------------------
Name: KEY_BufferOut -
Purpose: To retrieve a scan code from the key buffer data structure.
Passed: None.
Returns:
KEY_NULL if there is no key in the key buffer.
Notes:
------------------------------------------------------------------- */
UB8 KEY_BufferOut (void)
{
UB8 bCode;
if (bKeyCnt)
{
bKeyCnt--;
bCode = abKeyBfr[ bKeyBfrOutIdx ];
bKeyBfrOutIdx++;
if (bKeyBfrOutIdx >= KEY_BFR_SIZE)
bKeyBfrOutIdx = 0;
return( bCode );
}
else
{
return( KEY_NULL );
} /* if */
} /* KEY_BufferOut */
/* -------------------------------------------------------------------
Name: KEY_Decode -
Purpose: To decode keypad pins to scan code.
Passed: None.
Returns:
KEY_NULL if there is no key in the key buffer.
Notes: Keypad is active low.
------------------------------------------------------------------- */
UB8 KEY_Decode (void)
{
return( (~KEY_IOPORT) & KEY_MASK );
} /* KEY_Decode */
/* -------------------------------------------------------------------
Name: KEY_Hit -
Purpose: To check whether the key buffer is not empty.
Passed: None.
Returns:
TRUE if the key buffer is not empty.
Notes:
------------------------------------------------------------------- */
BOOL KEY_Hit (void)
{
return( bKeyCnt > 0 );
} /* KEY_Hit */
/* -------------------------------------------------------------------
Name: KEY_Init -
Purpose: To initialize the KEY module.
Passed: None.
Returns: None.
Notes:
KEY_Init() must be called before calling any other of
the user accessible functions.
------------------------------------------------------------------- */
void KEY_Init (void)
{
// Setup KEYPAD input !
#if (PLATFORM_CFG == PLATFORM_01_DMO1611A0)
// (01)VID540-100-027/BIT1611B0 (v1.00 2005/10/14 BIT1611B0 Demo Board)
KEY_iPOWER = 1;
KEY_iMENU = 1;
KEY_iSELECT = 1;
KEY_iUP = 1;
KEY_iDOWN = 1;
#elif (PLATFORM_CFG == PLATFORM_04_DMO1611S0)
// (04)PLATFORM_04_DMO1611S0 (VID502-002-031,BIT1611BS0)
KEY_iPOWER = 1;
KEY_iMENU = 1;
KEY_iSELECT = 1;
KEY_iUP = 1;
KEY_iDOWN = 1;
#elif (PLATFORM_CFG == PLATFORM_06_VTX0501)
// (06)PLATFORM_06_VTX0501 (BMW HS 2.1)
KEY_iPOWER = 1;
KEY_iMENU = 1;
KEY_iSELECT = 1;
KEY_iUP = 1;
KEY_iDOWN = 1;
#else
#error KEY.C - Invalid PLATFORM_CFG !
#endif /* PROJECT */
#if (KEY_AUTO_REPEAT)
bTimerKeyAuto = 0; /* For key auto repeat feature */
#endif // KEY_AUTO_REPEAT
#if (KEY_STILL_DETECTION)
// Pressed key duration !
bKEY_STILL_INTERVAL = KEY_STILL_INTERVAL;
bTimerKeyPressed = bKEY_STILL_INTERVAL;
#endif
KEY_BufferFlush();
fKeyReleased = TRUE;
bKeyScanState = KEY_STATE_UP;
#if (KEY_VR_AIN21)
bKEY_VR_ADJUSTMENT = KEY_VR_DEFAULT;
#endif
} /* KEY_Init */
/* -------------------------------------------------------------------
Name: KEY_Pressed - To check whether any keys are pressed.
Purpose: .
Passed: None.
Returns:
FALSE if no key pressed.
Notes:
------------------------------------------------------------------- */
BOOL KEY_Pressed (void)
{
return( (KEY_IOPORT & KEY_MASK) != KEY_MASK );
} /* KEY_Pressed */
/* -------------------------------------------------------------------
Name: KEY_Scan -
Purpose: To scan the keypad periodically.
Passed: None.
Returns: None.
Notes:
1) THIS ONE IS USUALLY CALLED FROM TIMER ISR ONLY
2) Local variables are allowed if it is NOT called by other ISRs
or code !
3) The duration is at least 30ms between each call of this scan
function for avoiding de-bounce failure.
------------------------------------------------------------------- */
void KEY_Scan (void)
{
#if (KEY_AUTO_REPEAT)
if (bTimerKeyAuto)
bTimerKeyAuto--;
#endif // KEY_AUTO_REPEAT
if (bTimerKeyPressed)
bTimerKeyPressed--;
#if (KEY_STILL_DETECTION)
if (bTimerKeyPressed == 1)
{
KEY_BufferFlush();
KEY_BufferIn(bLastKey | KEY_MASK_STILL);
#if (NO_RELEASE_AFTER_STILL)
fKeyNO_STILL = FALSE;
#endif
}
#endif // KEY_STILL_DETECTION
switch (bKeyScanState)
{
case KEY_STATE_UP:
if (KEY_Pressed())
{
bKeyScanState = KEY_STATE_DEBOUNCE;
#if (NO_RELEASE_AFTER_STILL)
fKeyNO_STILL = TRUE;
#endif
}
#if (KEY_STILL_DETECTION)
else
{
bTimerKeyPressed = 0;
fKeyReleased = TRUE;
}
#endif // KEY_STILL_DETECTION
break;
case KEY_STATE_DEBOUNCE:
if (KEY_Pressed())
{
KEY_BufferIn(KEY_Decode());
#if (KEY_AUTO_REPEAT)
bTimerKeyAuto = KEY_REPEAT_START_DELAY;
#endif // KEY_AUTO_REPEAT
bLastKey = KEY_Decode();
#if (KEY_STILL_DETECTION)
if (bLastKey == KEY_POWER)
bTimerKeyPressed = bKEY_STILL_INTERVAL;
#endif // KEY_STILL_DETECTION
bKeyScanState = KEY_STATE_REPEAT_START_DELAY;
}
else
{
bTimerKeyPressed = 0;
fKeyReleased = TRUE;
bKeyScanState = KEY_STATE_UP;
}
break;
case KEY_STATE_REPEAT_START_DELAY:
if (KEY_Pressed())
{
#if (KEY_AUTO_REPEAT)
if (bTimerKeyAuto == 0)
{
KEY_BufferIn(KEY_Decode());
bTimerKeyAuto = KEY_REPEAT_INTERVAL;
bKeyScanState = KEY_STATE_REPEAT_DELAY;
} /* if */
#endif // KEY_AUTO_REPEAT
}
else
{
#if (NO_RELEASE_AFTER_STILL)
if (fKeyNO_STILL)
#endif
{
KEY_BufferFlush();
KEY_BufferIn(bLastKey | KEY_MASK_RELEASE);
}
bTimerKeyPressed = 0;
fKeyReleased = TRUE;
bKeyScanState = KEY_STATE_DEBOUNCE;
} /* if */
break;
#if (KEY_AUTO_REPEAT)
case KEY_STATE_REPEAT_DELAY:
if (KEY_Pressed())
{
if (bTimerKeyAuto == 0)
{
KEY_BufferIn(KEY_Decode());
bTimerKeyAuto = KEY_REPEAT_INTERVAL;
} /* if */
}
else
{
#if (NO_RELEASE_AFTER_STILL)
if (fKeyNO_STILL)
#endif
{
KEY_BufferFlush();
KEY_BufferIn(bLastKey | KEY_MASK_RELEASE);
}
bTimerKeyPressed = 0;
fKeyReleased = TRUE;
bKeyScanState = KEY_STATE_DEBOUNCE;
}
break;
#endif // KEY_AUTO_REPEAT
default :
break;
} /* switch */
} /* KEY_Scan */
/* -------------------------------------------------------------------
Name: -
Purpose: .
Passed: None.
Returns: None.
Notes:
------------------------------------------------------------------- */
/* **********************************************************************
Description:
********************************************************************** */
/* %% End Of File %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% */