Retrocomputing Stack Exchange
Retrocomputing Stack Exchange

Questions tagged [zx-spectrum]

For questions about the different versions and products of the Sinclair ZX Spectrum computer

The Spectrum was a Z80-based microcomputer introduced in 1982.

It was the first product from Sinclair Research Ltd. to have a colour display.

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What was the reason for the ZX Spectrum's display bitmap layout?

I had a ZX Spectrum 48KB, whose display was a 256*192 monochrome bitmap (plus separate per-block color attributes). I remember the display bitmaps scan lines were laid out in memory in a weird way - This was evident when trying to render to the…
Jonathan
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Inglish parser on the Hobbit (1982 video game)

Most adventure games, to keep the parser simple, might just have some simple rules, which accepts verb + noun or a cardinal direction, and simple things like that. That's almost a CFG, so in Backus-Naur Form, a simple parser might look like: s =>…
Omar and Lorraine
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Are there any ZX Spectrum applications (mainly games or demoscene productions) that use a port other than $FE to access the ULA?

Although it is widely known that the ZX Spectrum ULA answers to any request to an even I/O address, all documentation state that the official port number to use should be $xxFE (where xx is any 8 bit number). I'm now updating my ULA core to add the…
mcleod_ideafix
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Measuring frame length on the ZX Spectrum

I've seen some small utilities for the ZX Spectrum, such as FUSETEST and MINFO, that report the number of T-states per frame. I can see these utilities don't rely on ROM checksums or anything like that to find out what machine they are running in…
mcleod_ideafix
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ZX Spectrum 48k Power Supply outputting 15V

I got a working ZX Spectrum 48k (issue 6a) with the original power supply. Before hooking up the power supply I tested with my multimeter to see if it was good. The power supply specifies it outputs 9V but my multimeter says 15V. To be safe I didn't…
JV Lobo
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What was the AMI SAGA and why wasn't it used it all ZX Spectrums?

This page has a note about a chip called AMI SAGA. Apparently it does the same job as the Ferranti ULA, but saves a little circuitry and runs cooler. What was this chip? Some kind of uncommitted logic array? Why would it run cooler, and save the…
Omar and Lorraine
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ZX Spectrum +2 not saving

I have a ZX Spectrum+2 with the built in tape deck. I can load tapes no problem, when I try to save, I get the border lines. When I try to reload the program I get nothing Any help would be greatly appreciated
Alistair
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ZX Spectrum fault

I was recapping my zx spectrum when after just replacing one specific capacitor it stopped working as before. The picture has multiple horizontal lines over the entire display. This is especially noticable with yellow, cyan and magenta as they show…
Steven McCorkindale
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