Scroll Down
Scroll Down
Is it possible to make the screen scroll down using basic on the ZX81, or only up? Like for a skiing program using scroll. Does the skier always have to be at the top of the screen for that simple BASIC trick, or is there a way to have the skier at the bottom?
Re: Scroll Down
In pure basic only scrolling up is possible in a reasonable time.
So Horace is always on top of the Hill, not at the bottom
So Horace is always on top of the Hill, not at the bottom
In theory, there is no difference between theory and practice. But, in practice, there is.
Re: Scroll Down
Is there an unpure BASIC way to do it, or does it need full machine code?
Re: Scroll Down
There are small machine code routines that offer scrolling in any direction and much more.
Search for
"Inline" BASIC Extensions
Search for
"Inline" BASIC Extensions
In theory, there is no difference between theory and practice. But, in practice, there is.
Re: Scroll Down
Here's an 8-way scroll routine in M/Code, it should be easy enough for you to adapt to your needs. 
- Attachments
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- 8WSCROLL.P
- (1.36 KiB) Downloaded 263 times
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