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legOS/kernel/dkey.c File Reference

debounced key driver. More...

Functions
		char dkey_timer	__attribute__ ((unused))
			single key state. More...
			__asm__ (" .text .align 1 .global _dkey_handler _dkey_handler: mov.b @_dkey_timer,r6l ; check debouncing timer==0 beq dkey_check dec r6l mov.b r6l,@_dkey_timer rts dkey_check: sub.b r6l,r6l ; generate button codes ; from PORT4/PORT7 in r6l mov.b @_PORT4,r6h bld #1,r6h bist #0,r6l bld #2,r6h bist #1,r6l mov.b @_PORT7,r6h bld #6,r6h bist #2,r6l bld #7,r6h bist #3,r6l mov.b @_dkey_multi,r6h xor.b r6l,r6h ; create mask of changed positions in r6h beq dkey_same mov.b r6l,@_dkey_multi and.b r6h,r6l ; mask out unchanged positions mov.b r6l,@_dkey mov.b #100,r6l ; set debouncing timer mov.b r6l,@_dkey_timer dkey_same: rts ")
			debouncing timer. More...
		wakeup_t	dkey_pressed (wakeup_t data)
			wakeup if any of the given keys is pressed.
		wakeup_t	dkey_released (wakeup_t data)
			wakeup if all of the given keys are released.
		int	getchar (void)
			wait for keypress and return key code. More...
Variables
		volatile unsigned char	dkey_multi
		volatile unsigned char	dkey
			multi-key state.

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Detailed Description

debounced key driver.

Author(s):

Markus L. Noga <markus@noga.de>

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Function Documentation

char dkey_timer __attribute__ ((unused))

single key state.

////////////////////////////////////////////////////////////////////////////

__asm__ (".text.align 1.global _dkey_handler_dkey_handler:mov.b@ _dkey_timer, r6l; check debouncing timer = =0 beq dkey_check dec r6l mov.b r6l, @_dkey_timer rts dkey_check:sub. b r6l, r6l;generate button codes;from PORT4/PORT7 in r6l mov.b@ _PORT4, r6h bld# 1, r6h bist# 0, r6l bld# 2, r6h bist# 1, r6l mov.b@ _PORT7, r6h bld# 6, r6h bist# 2, r6l bld# 7, r6h bist# 3, r6l mov.b@ _dkey_multi, r6h xor. b r6l, r6h;create mask of changed positions in r6h beq dkey_same mov. b r6l, @_dkey_multi and. b r6h, r6l;mask out unchanged positions mov. b r6l, @_dkey mov.b# 100, r6l;set debouncing timer mov. b r6l, @_dkey_timer dkey_same:rts")

debouncing timer.

////////////////////////////////////////////////////////////////////////////

wakeup_t dkey_pressed (wakeup_t data)

wakeup if any of the given keys is pressed.

wakeup_t dkey_released (wakeup_t data)

wakeup if all of the given keys are released.

int getchar (void)

wait for keypress and return key code.

key combinations not admissible.

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Variable Documentation

volatile unsigned char dkey_multi

volatile unsigned char dkey

multi-key state.

legOS-0.2.4 is released under the Mozilla Public License. Original code copyright 1998-1999 by the authors.