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;
; Piotr Fusik, 04.11.2001
; originally by Ullrich von Bassewitz and Sidney Cadot
;
; clock_t clock (void);
; unsigned _clocks_per_sec (void);
;
.export _clock, __clocks_per_sec
.importzp sreg
.include "atari.inc"
.proc _clock
ldx #5 ; Synchronize with Antic, so the interrupt won't change RTCLOK
stx WSYNC ; while we're reading it. The synchronization is done same as
@L1: dex ; in SETVBLV function in Atari OS.
bne @L1
stx sreg+1 ; Byte 3 is always zero
lda RTCLOK+2
ldx RTCLOK+1
ldy RTCLOK
sty sreg
rts
.endproc
.proc __clocks_per_sec
ldx #$00 ; Clear high byte of return value
lda PAL ; use hw register, PALNTS is only supported on XL/XE ROM
and #$0e
bne @NTSC
lda #50
rts
@NTSC: lda #60
rts
.endproc
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