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Vintage Computers Any vintage computer systems, calculators, video games etc., but with an emphasis on 1980s and earlier equipment.

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Old 1st Sep 2021, 9:54 pm   #41
Dave Moll
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Default Re: ZX Spectrum Issue 2 / new TVs

Nowadays the packaging would probably have to include some disclaimer along the lines of "not actual game image" as it's well beyond the abilities of a Spectrum!

edit: I should say that this relates to post no. 19. I hadn't spotted that there was a whole other page of posts.
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Old 4th Oct 2021, 8:51 pm   #42
Eidolon
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Default Re: ZX Spectrum Issue 2 / new TVs

Quote:
Originally Posted by Timbucus View Post
Of course you could go full HDMI as well... https://www.bytedelight.com/?product...o-complete-set
Based on what the various things I have come across with the modern ZX Spectrum Next, the original Spectrum has timings that don;t work properly over HDMI, and in the case of the Next, when it's connected via HDMI, the games run at a slightly wrong speed because of it.
I have no idea how the RF from the Spectrum will trnaslate via a HDMI convertor.
I'm pretty sure that the Spectrum Show on Youtube had something in one of the episodes about something that could be attached to original Spectrums to get a flatscreen tv friendly signal.

As an alternative, there is a very good Spectrum emulator on the Wii, which also allows key reassigning to a game controller, which is very good for games with bad key layouts, of which there are a fair few.

My Next won't work properly with my led flatscreen via rgb-scart, and I get very bad image tearing, I think it's something to do with the Next and the TV maybe being out of synch, and not refreshing the frames correctly. From what I can gather, the problem seems to be mostly the fault of the TV. I have yet to try it over VGA, that may solve the problem.
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Old 4th Oct 2021, 9:11 pm   #43
Timbucus
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Default Re: ZX Spectrum Issue 2 / new TVs

That is certainly the best way to use the Next is via VGA as the timing is cycle accurate in VGA-0 not all monitors will support that. In the higher VGA modes 1-6 they start to approach the HDMI timing and will again speed it up - that is the effect that a US user would have got with the 60Hz timing.

The one I linked to for original Spectrums actually uses a PI to track the screen changes into a buffer which is then rendered to the display so the timing is not a problem although there is probably a single frame of lag introduced.

I noticed ScottishColin asked why the Issue 2 was my favourite - I suppose as I had a lot of them originally and indeed now so I am familiar with them even though the colour adjustment is a pain - to an extend they represent an affordable older version as well as issue 1's are out of my reach... My original issue 1 was used 20 years ago as part of a Borg costume for my Son much to my shame.
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Old 5th Oct 2021, 4:48 pm   #44
Eidolon
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Default Re: ZX Spectrum Issue 2 / new TVs

I've just had Bikers Deluxe through for my Next. It's pretty good if you like racing games, although the angle of the road could have been chosen better, it makes it really difficult to see anything directly in front of you.
Interestingly, regarding the HDMI, running the game via that is more system intensive, and so it disables the in-game music.
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Old 5th Oct 2021, 6:00 pm   #45
Timbucus
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Default Re: ZX Spectrum Issue 2 / new TVs

This is a problem that affects all systems where the frame is tied to the display frequency - there are only a certain number of cycles available and less at 60Hz (as there are 10 more frames in the same second).

If you say swapped a UK Issue 2 ULA with the US ULA and then tried to run some games that pushed the envelope they could well crash as they will receive an interrupt before they finish processing the previous one depending on how they are coded - it sounds like bikers read the available frame time and decided what to sacrifice - the advantage of a modern system and awareness of the frame frequency issue. That is why VGA-0 is ideal as it is exactly 50 frames a second.

There is a similar effect where often the US experienced the games and sound running faster so they sound different and take different timings to play - this was a common problem on systems that were popular in both countries like the C64.
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