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Questions tagged [zx80]

The Sinclair ZX80 was a low cost home computer introduced in 1980.

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ZX Spectrum - guidelines for porting to PC and more are appreciated

I want to make a surprise for my father. Back in the 80s my father made a game for a custom clone (called Santaka) of the ZX Spectrum. I have all the digital files needed for it to work, but I'm ...
Sir Muffington's user avatar
15 votes
3 answers
2k views

Is there any significant difference in Sinclair BASIC of ZX80, ZX81 and ZX Spectrum?

I'm trying to write some programs from an old magazine that were specified to run on an ZX80/ZX81 but I'm using a Sinclair BASIC interpreter for the Spectrum. Is there any significant changes in BASIC ...
d'Arby's user avatar
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2 votes
1 answer
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Did the ZX80 RAM pack pass the expansion bus through?

The ZX80 only came with 1K of RAM, which had to be shared between program and screen memory, so many customers bought the Sinclair 16K RAM pack, which plugged into the expansion bus (the edge ...
rwallace's user avatar
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29 votes
3 answers
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Why did the ZX80 CPU run at only 3.25 MHz?

The Sinclair ZX80 used a Z80A running at 3.25 MHz. But this chip was rated for 4 MHz. Why was it run below rated speed? Apparently the master clock in the machine ran at 6.5 MHz, so the CPU clock ran ...
rwallace's user avatar
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6 votes
1 answer
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How did the ZX80 RAM pack use DRAM?

The Sinclair ZX80 was the most popular personal computer in Britain at the beginning of the 1980s, due to its low price which was enabled by extreme minimalism; it consisted of not much more than a ...
rwallace's user avatar
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7 votes
1 answer
630 views

Why is ZX80 much faster than Spectrum on Rugg/Feldman benchmarks?

If you look at the results of the Rugg/Feldman benchmarks, shown in this Wiki entry, you'll see that Sinclair ZX80 is much faster than Sinclair Spectrum on all tests despite the fact that both ...
neutrino's user avatar
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24 votes
2 answers
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How did the ZX80 store both a useful program and screen memory?

I have a vague recollection from my earliest days that the ZX80 only shipped with 1K of RAM. If this RAM was used to store both the program and the contents of the 32x24 screen, wouldn't that mean ...
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12 votes
2 answers
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Why does the ZX80 not produce a steady display signal?

As Tommy pointed out in my question about BASIC tokens on the ZX Spectrum, the ZX80 is a computer which does not produce a signal which is displayed steadily on the TV. It looks to me as if the CRT is ...
Героям слава's user avatar
11 votes
3 answers
841 views

ZX80 BASIC checking free memory

Did ZX80 BASIC have a way to check how much memory you were using and how much was left? Or otherwise: if you were writing a program on a machine with the RAM expansion, was there a way to tell ...
rwallace's user avatar
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