Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!ub!uhura.cc.rochester.edu!ee.rochester.edu!seah From: seah@ee.rochester.edu (David Seah) Newsgroups: comp.sys.apple2 Subject: Re: HIRES question Message-ID: <1991Feb5.010039.16335@ee.rochester.edu> Date: 5 Feb 91 01:00:39 GMT References: Distribution: comp Organization: University of Rochester Department of Electrical Engineering Lines: 53 In article nagendra@bucsf.bu.edu (nagendr! >Does anyone remember what the memory location is that tells what page >you're drawing on? Zero page location $E6 (230 decimal) tells you what memory page that Applesoft will use to draw on. For Hires Page 1, poke 230,32. For Hires Page 2, poke 230,64. >I wanted to do some 2 page animation with the old hires modes. and I >remember that it was something like poke -16xxx,32 to draw on page 1 and >poke -16xxx,64 to draw on page2 without showing those screens. >but I can't seem to remember the location numbers. Here's something out of the ancient book, "Apple Graphics and Arcade Game Design" by Jeffrey Stanton: 5 X1=0:Y1=0 10 rem clear both screens 20 home:hgr:hgr2:hcolor=3 30 rem now looking at page2 40 rem set drawing mode pointer (E6) to screen #1 50 POKE 230,32 51 rem clear screen #1 52 call 62450 60 for i=1 to 35 70 x2=int(rnd(1)*280) 80 y2=int(rnd(1)*192) 90 hplot x1,y1 to x2,y2 100 x1=x2:y1=y2 110 next i 120 rem look at screen #1 full screen 125 poke-16300,0:poke-16302,0 130 rem set drawing mode pointer (e6) to screen #2 135 POKE 230,64 136 rem clear screen#2 137 call 62450 145 for i=1 to 35 150 x2=int(rnd(1)*280) 160 y2=int(rnd(1)*192) 170 hplot x1,y1 to x2,y2 180 x1=x2:y1=y2 190 next i 200 rem look at screen #2 210 poke -16299,0 230 goto 50 All...what memories! :-) -- Dave Seah ^..^ | Analog Design Automation Research Group - Graphics & GUI | | University of Rochester, Dept. of Electrical Engineering | ////// Internet: seah@ee.rochester.edu ////// America Online: AFC DaveS //////