tic42val.asm

ADUC842 C程序集,包括ADC,DAC,PLL,PWM,WDT等程序．

;File: tic42val.a51
;Author: Eckart Hartmann Date:17/10/2003
;Development progress: Tic834.df
;
;TicVal==========Set and start interval counter.
;C Function prototype: char TicVal(char cVal, char cMode);
;Description of Function: Put interval counter in operation.
;User interface: Set first parameter to required interval count.
;		Set second parameter to choose clock source for interval counter
;		as follows:
;			0 for 128 clocks per second (HTHSEC)
;			1 for 1 clocks per second (SEC)
;			2 for 1 clocks per minute (MIN)
;			3 for 1 clocks per hour (HOUR)
;		Add 8 to the parameter for a single interval or else multiple
;			intervals are measured.
;		Call TicVal function.
;		TicVal zeroes interval counter sets required interval count
;			and clock source and starts interval counting.
;			Enables global interupt bit and TIC interupt on low priority.
;			When required interval is reached interupt TicInt is
;			executed.
;		returns TIMECON (guaranteed not zero).
;Robustness:
;Side effects: Starts TIC timer if not running already.
;
NAME TICVAL
$NOMOD51
 $IC(..kei842.inc) ; Parameter passing registers for Keil .
 $IC(..kei842.dat) ; SFR definition for Keil .
;
public _TicVal

?PR?_TicVal?TICVAL	SEGMENT CODE
	RSEG	?PR?_TicVal?TICVAL
;
_TicVal:
	anl	TIMECON,#0f1h	;Stop and clear interval counter.
	mov	a,cP2lc		;Choose single or multiple.
	anl	a,#8
	orl	TIMECON,a
	mov	a,cP2lc		;Choose clock source.
	anl	a,#03h
	swap	a
	anl	TIMECON,#0cfh
	orl	TIMECON,a
	mov	INTVAL,cP1l	;Set interval.
	orl	TIMECON,#3	;Start TIC.
	anl	IEIP2,#0afh	;TIC low priority
	orl	IEIP2,#4	; enabled.
	setb	EA		;Global enable.
	mov	cP1l,TIMECON	;Return TIMECON.
	ret
;
;Function End==========================================================Function End
END