MIDI through the ZXpand-AY joystick port maybe?

[sirmorris]

Just a random thought BECAUSE I DON'T HAVE ENOUGH ON MY PLATE ALREADY.

It might be possible to output midi on the AY board's DB9.

Is anyone familiar with PIC and would like to have a go?

[Moggy]

Writing as someone who has,since it inception, used MIDI professionally and semi professionally in retirement and loves the medium immensely but is technically stupid I say unto thee Charles this....

1) Whatever it is you have on your plate (probably something to do with bailing me out of yet another fine mess) Stop it at once and get your valet to do it.

2) Adopt a cross legged position on the floor of your mansions stateroom,take a slaking draught of good single malt and repeatedly chant the following...

"MIDI IS THE BEST THING THAT COULD HAPPEN TO A ZEDDY I WILL MAKE IT MY LIFE'S WORK TO COMPLETE THIS TASK AT THE EXPENSE OF ALL OTHERS"

Then having consumed more scotch than is good for you, just before you slump into unconscious incoherence you can take heart that such a gift to the zeddy would bring joy to all the musicians amongst our zeddy bretherin which at the last count consisted of Yerz,myself and a cairn terrier called Wilfred.

We could then poke that barmy midlander with a stick and persuade him to write a sequencer for it.

Seriously though Charlie great idea I just hope someone has the Latin for it.

[sirmorris]

Midi serial output is possible but like you say (or imply) it's only half the solution. It would be like the mouse hack - more of a curiosity than a truly usable feature

[Andy Rea]

an interesting read but not quite midi....

http://www.retrothing.com/2009/03/muzix ... stem-.html

however the speccy +2B and +3 had that cruddy string based music thingyma bob that can output midi.... some reverse engineering of the roms maybe...

and some techno zx spectrum style... https://www.youtube.com/watch?v=e26VDj_TE78

not sure if it's all channels at once or wheather there is some post mixing going on...

[Moggy]

Do it Andy do it!!
Go on you know you want to.

I have an old boss drum machine that uses The CV method mentioned in your first link,more of a synchronising switch-on switch-off thing than carrying any actual note information if I remember correctly..

[Andy Rea]

seems like if you want midi on a sinclair its best to go some sort of zx spectrum flavour, some hardware about, some software about.... oh and did i mention i dont know one end of a sausage from a midi interface let alone the protocol... i do know however that the sausage has an opto-coupler on the inputty bit

[Moggy]

You didn't know one end of an AY unit when you created that magnum opus the "Andy-tracker"

You are a discredit to the guild of glue gun users everywhere.

Now what about that decompiler you promised!?

The opto coupler is just to stop mixed voltages between synths various and other gubbins doing silly things.

[1024MAK]

MIDI from a low level data point of view is just a serial link using a specific clock frequency. There are bit-bashed serial code routines for PIC microcontrollers. Sorting out the electrical side of a MIDI interface is not hard. The most difficult bit is getting the ZX81 to communicate the MIDI data to the PIC microcontroller and getting the PIC to do all it's normal stuff at the same time.

If that can be sorted, it actually makes it a bit better than the ZX Spectrum 128k /+2 /+2A/+2B/+3/+3B machines, as the poor old Z80 CPU has to do the parallel to serial conversions AND bang it out a bit at a time with the timing exactly right.

Mark

[Andy Rea]

Decompiler---- promised.... to think about it.... still thinking mwhahaha.... Actually if you want the samples extracting thats easy.... as for recreating the patterns well thats kinda like playing it without making any noise... and its a long time since i played with that player....

So Mark / SirMorris it would be the Pic doing the bit banging ? if So then maybe it is possible, with the zeddy just instructing the Pic the take file blahblah see if it contains a midi header chunk and if so go ahead and start spitting bits out, until you reach the end or recieve a message to stop.

just my 2p

[sirmorris]

Yep, the PIC would be outputting software serial. It has a hardware UART but the pins are elsewhere. There is a software serial library, but the serial end of things isn't the difficult bit. It's outputting data from an arbitrarily formatted binary file in a protocol sufficient to render the machinery on the other end of the cable operational. Capische?