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Article #118 (419 is last): Newsgroups: freenet.sci.comp.atari.questions From: visitor Subject: VERTICAL BLANK VECTORS Date: Sun Jul 30 09:23:17 1989 How do you set up a VBI? Every time I try it comes out wrong. thanx. /s ** Answered by JOHN SUCHY (aa271) on Sat Jun 27 00:31:55 1987 ** Since you have been having some form of results--even bad ones--I'll assume that you know about the Vector, or "address of subroutine" associated with the Verticle Blank Interrupt (VBI, things that happen while the TV screen can't see them). In that case you are probably forgetting to branch back to the standard VBI routines at the end of your code. A JuMP to the original address in the VBI vector should do it. Let me know whether this helps. Your Co-sysop John E. Suchy aa271 Thanks for asking.