Futuro MZ by Genesis Project

Is there such a thing as an MZ demoscene?
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mz-80a
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Re: Futuro MZ by Genesis Project

Post by mz-80a »

Excellent. Thanks for that explanation, very detailed. I remember you mentioning it before in regards to making changes to the display on the horizontal blanking period etc I hope to try this out properly on my MZ-80A soon.
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hlide
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Re: Futuro MZ by Genesis Project

Post by hlide »

yes, it looks MZ-80 A has a similar scheme but I didn't see it clearly in the service manual. If true, MZ-80 A may benefit of the same tricks to make fast display.
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Re: Futuro MZ by Genesis Project

Post by hlide »

Also, the snow effects on MZ-80 K is merely due the fact that Z80 is reading/writing in VRAM while video circuit is reading bytes from VRAM precisely because there is no setting /WAIT to 0 when drawing during horizontal rasterline.
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Re: Futuro MZ by Genesis Project

Post by mz-80a »

So the facility for /WAIT was available for the 80K but wasn't implemented?
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Re: Futuro MZ by Genesis Project

Post by hlide »

The /WAIT facility is for any device which needs to supply it and it is a common Z80 signal: for instance, when you plug you own PCB in the expansion bus (/EXWAIT signal) and want to make the CPU able to adjust to slow chips (/EXWAIT signal is connected to Z80 /WAIT signal). MZ-80 K has no LSI to handle mutual storage access exclusion. MZ-80 A is a mistery for now (I hope @psmart can tell me more about it).
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