Could Amstrad have made tapes play faster?

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Wall_Axe
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Could Amstrad have made tapes play faster?

Post by Wall_Axe »

Could Amstrad have made the tape deck play the tapes faster and adjust the ROM to read the info and load a game quicker?
lets say twice as fast ?
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PROSM
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Re: Could Amstrad have made tapes play faster?

Post by PROSM »

They probably could have made the internal tape decks play faster, but this would have caused problems for software with custom loaders, since the modifications to the ROM wouldn't make a difference to the speed at which the custom loader expected the data. In addition to this, at higher speeds, the reliability of the loading process tends to decline, especially depending on the condition of the internal tape deck itself.

Some companies did try to do such a thing, like Challenge Research's SPRINT tape deck, which played tapes at 4X speed and replaced the regular ROM routines with ones that were programmed to load at this speed. However, it could not use software with custom loaders, because these did not rely on ROM, and so were not programmed to load at the higher speed.

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Re: Could Amstrad have made tapes play faster?

Post by Ralf »

YES ;)

But it would make most games with custom loader unable to load. So you would need to have some real switch for different speeds of tape recorder.

And with some bigger speed increase the loading would become unreliable (if it ever was reliable :lol: ) You would get a lot of "Tape loading error" messages.

I recall that there were some "turbo loading" systems done for Commodore C64 and 8-bit Atari but won't tell you how it worked in details.
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Re: Could Amstrad have made tapes play faster?

Post by Wall_Axe »

oh that SPRINT loader is awesome.

Maybe if they had introduced that as standard Ocean wouldve put a normal loader on Side B of the tape :D
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MonkZy
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Re: Could Amstrad have made tapes play faster?

Post by MonkZy »

I have been playing around with Otla. The tool converts .tzx files into a .wav you can play into a spectrum. I have used it to load the Hobbit into a 48k spectrum in 34 seconds via the regular EAR connection. The baud is lifted from 1200 to 12600 and it works flawlessly. Obviously this rate is way too quick for analogue cassettes, but it shows what the upper limits are on the cassette interface. Maybe they could have made a mini CD player :)

Links :

http://mrpjevans.com/2013/04/load-zx-sp ... n-seconds/

http://code.google.com/p/otla/
Wall_Axe
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Re: Could Amstrad have made tapes play faster?

Post by Wall_Axe »

yeah that is impressive, he says that playing a tape at that speed would stretch out the tape or something (thinking in terms of eighties tech.)

It is shocking to realise that the z80 can actually load data into the ram at astonishing speeds. After using slow tapes for years.
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Re: Could Amstrad have made tapes play faster?

Post by AndyC »

MonkZy wrote: Wed Feb 14, 2018 10:51 pm Obviously this rate is way too quick for analogue cassettes, but it shows what the upper limits are on the cassette interface. Maybe they could have made a mini CD player :)
Isn't that more or less what the Codemasters' CD system did? Although I think via the joystick port rather than cassette interface (probably as much because you had to load the loader via tape as anything else)
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Re: Could Amstrad have made tapes play faster?

Post by 1024MAK »

Err, both the Z80A and the 6502 (the 2MHz version) can actually "load" data to RAM from a high speed serial stream much faster than most people think.

And Sinclair had already come up with a "high speed" loading system - the microdrive :P

Amstrad however, with the ZX Spectrum line were aiming for compatibility and low manufacturing cost. So although a faster tape loading system was possible, it is not something they would have had any interest in. Plus of course, they introduced the +3 with a disk drive.

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