does the jupiter ace do pixel exact character printing?

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the7778
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does the jupiter ace do pixel exact character printing?

Post by the7778 »

all of the characters seem to move in 8 pixel squares. was there a way or was the jupiter ace capable of moving in single pixel jumps? i can see from a plotting demo that it can draw lines, circles, etc.

i know this could probably done using bit shifting but could it be done natively?
Last edited by the7778 on Fri Nov 25, 2022 5:19 pm, edited 1 time in total.
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1024MAK
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Re: does the jupiter ace do pixel exact character printing?

Post by 1024MAK »

It has a character mapped display. The video RAM is only 1K bytes.

A layout is here.

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the7778
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Joined: Sat Oct 05, 2019 5:14 pm

Re: does the jupiter ace do pixel exact character printing?

Post by the7778 »

1024MAK wrote: Fri Nov 25, 2022 5:06 pm It has a character mapped display. The video RAM is only 1K bytes.

A layout is here.

Mark
so no then? i guess you would have to use bit shifting
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1024MAK
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Re: does the jupiter ace do pixel exact character printing?

Post by 1024MAK »

You can I believe redefine the pixel grid for each character. The total RAM for the character pixel data is 1K bytes (this is in addition to the character mapped layout video RAM). Think of it as user defined characters (UDG).

But no, it does not have true bit mapped graphics like a ZX81 hi-res display or a ZX Spectrum.

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
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