contiki/platform/pc-6001/dev/clock.S

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;;;
;;;
;;; clock.S
;;;
;;; retrieve tickcount from PC-6001's internal timer
;;;
;;; @author Takahide Matsutsuka <markn@markn.org>
;;;
;;; $Id: clock.S,v 1.1 2007/09/11 12:12:59 matsutsuka Exp $
;;;
.globl _clock_time
.area _GSINIT
;; ---------------------------------
;; unsigned long clock_time();
;; __BCDEHL____
;; return long value as (DE, BC)
;; ---------------------------------
;; this function uses PC-6001's internal timer
;; which counts up 2 per 1/512 sec.
.area _CODE
_clock_time:
ld hl, #0xfa28
ld c, (hl)
inc hl
ld b, (hl)
inc hl
ld e, (hl)
inc hl
ld d, (hl)
ld l, c
ld h, b
ret