ZX Spectrum - Multi I/O Board - NEW

A place to discuss the ZX80's and ZX81's younger brother - the Sinclair ZX Spectrum
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IanJ
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Joined: Tue Oct 14, 2014 11:10 pm

ZX Spectrum - Multi I/O Board - NEW

Post by IanJ »

Hi all,

A ZX Spectrum owner since 1982 (early Issue 2) I dug her out of the loft and set to work designing and building an interface board for fun. I came up with a Multi I/O interface that gives the Spectrum:-

4 analogue inputs - ADC - 12 to 18bit configurable
4 analogue outputs - DAC - 16bit
24 digital I/O
I2C bus interface

Like I said, I did it for fun with no real plans to sell any..........but thought you guys might like to have a look.

http://www.ianjohnston.com/index.php?op ... cle&id=105

Ian.

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RWAP
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Re: ZX Spectrum - Multi I/O Board - NEW

Post by RWAP »

Your experience with this might help with the Covox board for the ZX81 - see viewtopic.php?f=6&t=1485
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stefano
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Re: ZX Spectrum - Multi I/O Board - NEW

Post by stefano »

The best known DAC audio application for the Spectrum was the SpecDrum.
Someone was able to change its output ports and redirect to the Disciple printer port with the "Covox" style DAC on it.

The digital outputs could perhaps be driven by my program for the "Psychedelic Lights", provided you build also an opto-insulated booster for the lamps.. mine had TIC216 triacs and was great, the software was respecting the alternate current phase thus it could handle intermediate light levels and flashes with no frequency-beating problems.
I recently wanted to see it running again, so I linked the 'frontpanel' library to the FUSE emulator (see attachment).
FUSE running my Psychedelig Light program
FUSE running my Psychedelig Light program
psy.jpg (39.49 KiB) Viewed 6066 times
To be totally honest it is not bound to the IN/OUT ports, it reacts to POKEs in the 8192->16383 range, which makes it compatible to also to the ZX81 BASIC.
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