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oldtime
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oldtime
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.PAG 'TIME 9/09/81'
;***********************************
;
; TIME AND ALARM ROUTINES FOR 6526
;
;***********************************
;
; RDTIM - READ THE TIME
; .Y = (BIT7=AM/PM,BITS4-0 HRS)
; .X = (BITS5-0 MINUTES)
; .A = (BITS5-0 SECONDS)
;
RDTIM LDY CIA+TODHR ;LATCH TOD
LDX CIA+TODMIN
LDA CIA+TODSEC
BIT CIA+TOD10 ;TO RESTART TOD
RTS
;
; SETTIM - SET TOD AND ALARM
; C-SET => SET ALARM
; C-CLR => SET TOD
; REGISTERS SAME AS RDTIM
; * THESE ROUTINES HAVE 1 SEC RESOLUTION
;
SETTIM PHA
ROR A ;SET BIT ACCORDING TO CARRY
AND #$80
ORA CIA+CRB
STA CIA+CRB
LDA #0 ;SET TOD10'S TO ZERO
STA CIA+TOD10 ;WHICH STOPS TOD
PLA
STA CIA+TODSEC
STX CIA+TODMIN
STY CIA+TODHR ;RESTART TOD
RTS
.END