S-BASIC Screen Scrolling

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mz-80a
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S-BASIC Screen Scrolling

Post by mz-80a »

Is S-BASIC really wasting precious memory keeping a copy of the screen so that you can scroll a BASIC listing back into view again when it's disappeared off the top of the screen? (Like the MZ-80A, except the 80A actually has 2KB of VRAM especially for this purpose).
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hlide
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Re: S-BASIC Screen Scrolling

Post by hlide »

S-Basic for MZ-700? I'm not sure about what you mean by wasting precious memory because there is no way else to do so. MZ-80 A and maybe MZ-1200 are the only machines able to scroll between two pages through hardware. MZ-700 may have a 2KB VRAM but the second page is useless because you need to deal with intra-VRAM transfers which has the worst performance.
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mz-80a
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Re: S-BASIC Screen Scrolling

Post by mz-80a »

Yep, a waste of memory then which could be put to better use for more space for BASIC programs. Took me ages to work out that you could scroll the screen up with SHIFT - UP :D It surprised me though because I assumed the 700 didn't have the 2KB VRAM which the 80A has.
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