Playing background music with AY Units

Anything Sinclair ZX Basic related; history, development, tips - differences between BASIC on the ZX80 and ZX81
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RWAP
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Playing background music with AY Units

Post by RWAP »

Thanks to Yerzmyey, the World of Spectrum boards have started a short discussion on the AY features for the ZX81 - see http://www.worldofspectrum.org/forums/s ... hp?t=37867

One of the questions was about how to play background music in games....

Over to SirMorris and Andy here....
sirmorris
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Re: Playing background music with AY Units

Post by sirmorris »

Andy - what kind of time are we talking about to run a cycle of the player? Would there be any CPU left for game code? If necessary what would could be done to reduce the overhead?
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Andy Rea
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Re: Playing background music with AY Units

Post by Andy Rea »

Erm.... the Current STC player is approx on average around 2500 cycles so in slow mode that equates to around 1/4 of available program executuion time. Per tv FRAME.

PT3 player on the other hand averages around 6000 ! cycles....

So erm yeah use the STC if you can.

Andy

P.S of course you need a suitable interrupt handler to keep everything in sync :-)
what's that Smell.... smells like fresh flux and solder fumes...
sirmorris
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Re: Playing background music with AY Units

Post by sirmorris »

Aaah that's better, I remember you were saying that sometimes the IRQs would overlap when playing PT3s.

I think I'm going to have to have a try :)

C
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BrunoFlorindo
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Re: Playing background music with AY Units

Post by BrunoFlorindo »

Back after a loooong time without a PC with internet connection. Glad to see the recent developments in AY hardware and software!

Still waiting to hear the Zeddy playing digital music. ;)
Moggy
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Re: Playing background music with AY Units

Post by Moggy »

BrunoFlorindo wrote:Back after a loooong time without a PC with internet connection. Glad to see the recent developments in AY hardware and software!

Still waiting to hear the Zeddy playing digital music. ;)
Hi Bruno nice to see You back again.

I don't know why but I always thought You had a ZONX-81 unit amongst Your collection, if not then raid the cookie jar for a ZXpand and AY unit (or just the xpand with any ZONX type unit) and get creating. :D

Here's something I knocked up on the zeddie then mixed with guitar and a bit of Yamaha AWM.

The bass, drums, twiddly bits and melody line were all done on the 81 using Andy Reas' tracker.

It can be done honestly.


Regards.

Moggy.
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