Subject: Re: [stella] VSYNC in 9 bytes From: "Thomas Jentzsch" <tjentzsch@xxxxxx> Date: Fri, 03 Sep 2004 12:28:48 +0200 |
Edwin Blink wrote:: > ;generates vertical sync pulse for 3 full scanlines. > ;VBLANK should be set by the overscan code and is not set here > > LDA #$0E ;each '1' bits generate a VSYNC ON line (bits 1..3) > VSLP1 STA WSYNC ;1st '0' bit resets Vsync, 2nd '0' bit exit loop > STA VSYNC > LSR > BNE VSLP1 ;branch until VYSNC has been reset Very nice indeed for maximum compact code. But it should be mentioned that it wastes one whole scanline, which sometimes might be very useful. So, who has an optimal solution for that? 10 bytes maybe? Have fun! Thomas _______________________________________________________ Thomas Jentzsch | *** Every bit is sacred ! *** tjentzsch at web dot de | ____________________________________________________ Aufnehmen, abschicken, nah sein - So einfach ist WEB.DE Video-Mail: http://freemail.web.de/?mc=021200
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