ZX81 to ZX Spectrum conversion possible

Discussion about ZX80 / ZX81 Software
nama
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ZX81 to ZX Spectrum conversion possible

Post by nama »

Is there an easy way to convert ZX81 programs to run on a 48k ZX Spectrum?

Thanks

Phil
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bobs
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Re: ZX81 to ZX Spectrum conversion possible

Post by bobs »

I doubt there is an easy way, due to the differences between the machines. The format of the display buffer is completely different, and RAM of an '81 sits in the same place as the display buffer of the Spectrum, and so there is a big mismatch there.

I do believe however that there are emulators for the Spectrum which do a passable job.
Bill H
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Re: ZX81 to ZX Spectrum conversion possible

Post by Bill H »

nama wrote:Is there an easy way to convert ZX81 programs to run on a 48k ZX Spectrum?

Thanks

Phil
I think it depends on the program, if it is all basic or mixed basic and ml or all ml. If it is graphics based or text based. Does it take advantage of features on the zx81?

Bill H
nama
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Re: ZX81 to ZX Spectrum conversion possible

Post by nama »

Well, I was thinking to convert my Chopperdrop 3000 program to the Spectrum. Originally written in BASIC then compiled using a basic compiler.

http://web.mac.com/lord_philip/sinclair ... _3000.html

So I could start with converting just the BASIC to the Spectrum and then compiling it again from there. Is there an easy way to convert the basic? Does any software exist to do this? Bill mentioned an emulator, but I'm not sure what this exactly means.

Cheers

Phil
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bobs
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Re: ZX81 to ZX Spectrum conversion possible

Post by bobs »

As a purely BASIC program that should convert pretty easily - if you have the program in a TXT file then that can be converted to a Spectrum emulator file pretty easily (I use BAS2TAP for this). As that converts the text it will point out any errors which need to be fixed, but there shouldn't be too many. After that you should have something which runs, but won't not look very pretty, as if you have used any character code values in your game those will be completely different on the Spectrum. You'll also need to fix the locations of any system variables you may have used.

Once you have that working, you'd need to add all the Spectrum-goodness - UDGs to replace the block Zeddy graphics, colour, sound, redefinable keys and joystick support, to name but a few.
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BrunoFlorindo
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Re: ZX81 to ZX Spectrum conversion possible

Post by BrunoFlorindo »

Oh man, how did I miss this?

Instead of converting software, you can run it!

Any 48K Speccy with an Interface 2 and a ZX81 emulator cartridge will do. A 128K +2A, +2B or +3 can also run ZX81 software without any additional hardware. Lookup Paul Farrow's website and you'll see. There is a topic on WOS about this, and I have some ZX81 games that I play on my Spectrum emulators!
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Paul
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Re: ZX81 to ZX Spectrum conversion possible

Post by Paul »

Sorry for coming into this discussion so late.
Om my 48K Spectrum I had a program called slowloader. It loads zx81 programs into speccy (on real hardware by tape!)
then you can save it as a spectrum program. I wonder if it can be found in the net. Otherwise I still have the cassette somewhere in my basement. Pm me if necessary.
Greets
Paul
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Paul
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Re: ZX81 to ZX Spectrum conversion possible

Post by Paul »

Have a look at WOS. Now you know the name it should be easy. I googled "slowloader zx81"
In theory, there is no difference between theory and practice. But, in practice, there is.
dr beep
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Re: ZX81 to ZX Spectrum conversion possible

Post by dr beep »

BrunoFlorindo wrote:Oh man, how did I miss this?

Instead of converting software, you can run it!

Any 48K Speccy with an Interface 2 and a ZX81 emulator cartridge will do. A 128K +2A, +2B or +3 can also run ZX81 software without any additional hardware. Lookup Paul Farrow's website and you'll see. There is a topic on WOS about this, and I have some ZX81 games that I play on my Spectrum emulators!
And you don't mention my ZX81EMUL running ZX81 MC on a ZX Spectrum?
Download on WoS (Slowloader included)
Prime
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Re: ZX81 to ZX Spectrum conversion possible

Post by Prime »

BrunoFlorindo wrote:Oh man, how did I miss this?

Instead of converting software, you can run it!

Any 48K Speccy with an Interface 2 and a ZX81 emulator cartridge will do. A 128K +2A, +2B or +3 can also run ZX81 software without any additional hardware. Lookup Paul Farrow's website and you'll see. There is a topic on WOS about this, and I have some ZX81 games that I play on my Spectrum emulators!
Yeah I converted one of my Spectrum +2A machines to run Paul's ZX80/81/Ace code just by setting jumpers, works a treat.

Cheers.

Phill.
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