Chroma 81 - SCART and Colour interface for the ZX81

Discussions about Sinclair ZX80 and ZX81 Hardware
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1024MAK
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by 1024MAK »

I do not yet have my Chroma 81, as I am waiting for Paul to let me know about some work he is doing on SPECTRA, which will require me returning my SPECTRA boards to him. The idea being he sends the Chroma 81 with the SPECTRAs when they are returned to me.

So don't fix the issue too quickly, it saves me dribbling all over the floor :lol:

Mark
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stefano
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by stefano »

>Is it an issue of my "modern" LED-TV??? (despite the SPONZYROM-display is stable?)
It could be, or perhaps we're sending out a non-standard signal which the LED-TV doesn't like.. you could try by POKEing the MARGIN system variable and making it work with NTSC scanlines, probably it is nonsense but it comes at a little cost.

>Am I the only one who ist playing around with Chroma81 and real hardware? Does no one other can report about his experience?
Not me :( but Perhaps you can understand a little more with the same TV connecting it via a composite or RF output ?
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siggi
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by siggi »

Hi Stefano
as written above, it makes no sense to poke MARGIN, because it is reset 50/60 times per second to the value given by the ULA 50/60Hz input.

But one of my test-zeddies has Andy's ULA 2: using POKE 101,4 it can be set to 60 Hz mode. And then at least one game (wall, b/w version) has a stable picture even at the LED-TV using the SCART input :D

BTW: the joystick-version of WALL does not allow fast horizonal moves (like the older keyboard version), so it is often not possible to reach the ball ..

Siggi
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stefano
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by stefano »

fast move: have you tried using the "fire" button ?

WRX on SCART: do you mean the chroma lib and the wrx give different results when run on that zeddy ?
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siggi
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by siggi »

stefano wrote:fast move: have you tried using the "fire" button ?
I selected the "cursor" joystick and used Chroma's joystick-port (Chroma unses cursor keys; FIRE gives key "0"). I don't have a joystick connector on ZXPAND.
WRX on SCART: do you mean the chroma lib and the wrx give different results when run on that zeddy ?
No, the pure B/W version of WALL (only for keyboard) and the colored version both "jump" on my LED TV/SCART and are stable on my CRT TV/SCART

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siggi
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by siggi »

Hi Stefano
since the HIRES routine of SPONZY-ROM gives a stable picture even on my sensitive LED TV: perhaps you could check, what the difference to the hires routine of z88dk is?

Siggi
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bobs
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by bobs »

I've been talking to Paul (Fruitcake), and we're going to get Chroma colour into my next game - REBOUND. There's a thread detailing the alpha version - which you can download - here:

viewtopic.php?f=4&t=1544

And the first draft of the game looks rather sweet with colour. :)

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Bob.
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chernandezba
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by chernandezba »

Hi

I'm happy to announce that my ZX80/81/Spectrum emulator, ZEsarUX, has now Chroma 81 support
I'm testing it on the snapshot version, no stable version yet but soon will release a new version

Cheers
Cesar
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olofsen
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by olofsen »

The game 2048 or 800 in hex presents a nice demo of Chroma's attributes display file mode :)
Attachments
zx0800.p
Updated version; for Chroma although it also works in B/W, 16K.
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Last edited by olofsen on Fri Dec 26, 2014 2:31 pm, edited 2 times in total.
Fruitcake
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Re: Chroma 81 - SCART and Colour interface for the ZX81

Post by Fruitcake »

olofsen wrote:2048 or 800 in hex presents a nice demo of Chroma's attributes display file mode (although it also works in B/W) :)
I've tested the program with a real Chroma interface but don't see any colours displayed...
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