Mercurial > repos > blastem
view fib.s68 @ 710:4cd8823f79e3
First pass at emulating a vscroll latch. Titan's Overdrive demo seems to depend on the scroll value being latched early in the line before the HINT gets a chance to change it
author | Michael Pavone <pavone@retrodev.com> |
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date | Sat, 16 May 2015 23:04:57 -0700 |
parents | f664eeb55cb4 |
children | 2455662378ed f7fe240a7da6 |
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dc.l $0, start start: moveq #36, d0 bsr fib illegal fib: cmp.l #2, d0 blt base subq.l #1, d0 move.l d0, -(a7) bsr fib move.l (a7), d1 exg d0, d1 move.l d1, (a7) subq.l #1, d0 bsr fib move.l (a7)+, d1 add.l d1, d0 rts base: moveq #1, d0 rts