check_battery.asm

胎压检测发送端汇编源码-tpms-transmitters

;/* LVI status check routine                      */
;/* V0.1   17 July, 2002 Jeff Burgess             */
;/* Called with:  jsr    SEND_BYTE                */
;/* Returns:      STATUS[7,6] containing the data */
;/*               from LVISR[7,5] respectively.   */
;/* (c) 2002 Motorola                             */

Check_battery:
        psha
        lda     LVISR
        sta     T3
        brclr   LOWV,T3,Chk_dead
        bset    6,STATUS

Chk_dead:
        brclr   LVIOUT,T3,Not_dead
        bset    LVIOUT,STATUS
        
Not_dead:
        pula
        rts