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adapted to Kick Assembler, some documentation update

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FeralChild64 committed 2019-09-07 12:35:21 +02:00
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commit de27124b4f
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c64/kernal/settim.s
+15 -15
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@@ -1,27 +1,27 @@
;;
;; Official Kernal routine, described in:
;;
;; - [RG64] C64 Programmer's Reference Guide - page 299/300
;; - [CM64] Compute's Mapping the Commodore 64 - page 232
;;
;; CPU registers that has to be preserved (see [RG64]): .A, .X, .Y
;;
//
// Official Kernal routine, described in:
//
// - [RG64] C64 Programmer's Reference Guide - page 299/300
// - [CM64] Compute's Mapping the Commodore 64 - page 232
//
// CPU registers that has to be preserved (see [RG64]): .A, .X, .Y
//
settim:
SETTIM:
;; Disable interrupts for the duration of the routine, to prevent
;; jiffy clock update while changing it's values
// Disable interrupts for the duration of the routine, to prevent
// jiffy clock update while changing it's values
sei
;; Store the jiffy clock state
// Store the jiffy clock state
sty TIME + 0
stx TIME + 1
sta TIME + 2
;; Enable interrupts. More elegant solution would be pha + sei + ... + pla,
;; but (checked by running a test program) original ROM routine always
;; leaves IRQs enabled.
// Enable interrupts. More elegant solution would be pha + sei + ... + pla,
// but (checked by running a test program) original ROM routine always
// leaves IRQs enabled.
cli
rts