;*************************************************************************; An 8051 Based Web Server; keypad.a51: driver code for keypad; By Mason Kidd 10/25/01;*************************************************************************$NOMOD51$INCLUDE(reg515.inc)name		keypadpublic	kbdinit, keypadi, keypresssd_keypad		SEGMENT	DATA			RSEG sd_keypadkeypress:	DS	1  			sc_keypad		SEGMENT	CODE			RSEG	sc_keypad 					USING 0               kbdpt	equ	30h      	; value for P2 to access keyboardkbdtbl: 	db	'123C456D789EA0BF'kbdinit:	setb	IT1			; extern int 1 falling edge	setb	EX1			; enable external interrupt	retkeypadi:	push	acc	push	psw	push	dph	push	dpl	push	p2	mov	dptr, #kbdtbl		; point to translation table	mov	p2, #kbdpt		; point to keyboard	movx	a, @r1	anl	a, #00011111B		; mask lower 5 bits	movc	a, @a+dptr		; translate to character code	mov	keypress, A	pop	p2	pop	dpl	pop	dph	pop	psw	pop	acc	reti     		end