Path: utzoo!utgpu!watmath!clyde!att!rutgers!apple!bionet!agate!saturn!ucscb.UCSC.EDU!lechner From: lechner@ucscb.UCSC.EDU (Eric Lechner) Newsgroups: comp.sys.cbm Subject: C64 text screen Summary: wanted: method to swap text screens in memory Keywords: text xcreen page swapping Message-ID: <5673@saturn.ucsc.edu> Date: 8 Dec 88 09:35:55 GMT Sender: usenet@saturn.ucsc.edu Reply-To: lechner@ucscb.UCSC.EDU (Eric Lechner) Organization: University of California, Santa Cruz; CATS Lines: 19 I am writing an assembly language "life" program and would like to do this: It needs to alternate between two screens, without copying the screen (due to time considerations. I am trying to optimize running time). I would like to keep each screen in a different place in memory, so that I need only change the pointer to the text screen. I have tried the 128 programmer's reference guide, and have tried altering location 648 (a page pointer to the top of the text screen) but the display does not change when I change that pointer. What am I doing wrong? Is there a pointer in the video chip that I need to alter as well as the other pointer? Am I overlooking anything else, as well? Any help will be appreciated. Eric ------------------------------------------------------------------------------- Eric Lechner 115 Seton Way Santa Cruz, CA 95060 lechner@ucscb.ucsc.edu ...ucbvax!ucscc!ucscb!lechner