Jetboot Jack Posted July 31, 2002 Share Posted July 31, 2002 Hi! Does anyone have a "nice" VBI vertical scrolling routine they would like to share? sTeVE Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted July 31, 2002 Share Posted July 31, 2002 Hi Steve, Depends on what you are scrolling? If you have a graphics mode (line at a time) memory layout then get the VBI to adjust the dlist's 'load memory' pointer, e.g. DLIST: .byte $70,$70,$70,$4E LM_PTR: .word SCR_MEM .byte $0E,$0E etc You can get clever and shuffle some LM pointers through the dlist such that you reuse the memory you're not displaying In a character based display you'll need to use the scroll registers to scroll things smoothly and then adjust the LM pointer(s) when reseting the scroll register. Regards, Mark Quote Link to comment Share on other sites More sharing options...
Jetboot Jack Posted August 1, 2002 Author Share Posted August 1, 2002 Mark, I have several simple MC scrolling routines that I'm tinkering with, but was wondering if anyone has a favorite for a 40 or 48 byte wide screen, using data laid out contigiously in RAM... My horizontal routines were never very good, so I thought I'd tackle some vertical ones and was wondering if anyone had a "best".... sTeVE Quote Link to comment Share on other sites More sharing options...
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