looking for an IEE488 midi adapter

[rorypoole]

Any one know where I can find an IEE488 to midi adapter or circuit diagrams for one for my commodore 4016 or 8032?

 

[sjgray]

Any one know where I can find an IEE488 to midi adapter or circuit diagrams for one for my commodore 4016 or 8032?

Never heard of such a thing. There are IEEE to SERIAL (RS-232) Adapters (Like the ADA series), but MIDI requires a specific speed, which may or may not be supported, and you would need to make a custom cable. The PET does not have any special chip for serial communications so it would all have to be done in software.

You might have more luck trying to make your own MIDI adapter using a UART or ACIA chip (like the MOS 6551) mapped directly into the PET address space. I'm sure there are some C64 ACIA cartridges (swiftlink?) with schematics that could be adapted. Then... what software can you use to make it all go?

Steve

 

[carlsson]

Weren't there RS-232 adapters for the user port, just like on the VIC/64? I seem to recall I have come across and even sold/donated some. But as you say, there is another step from RS-232 to MIDI, and then there is the use case to wonder about. Technically I'm sure it is doable, but by whom and for what purpose?

 

[billdeg]

Here is some info about the USER port, as a serial-like device, with a link to an article from Byte December 1980 which touches on how to set up a multi machine game using the user port, etc.

http://vintagecomputer.net/browse_thread.cfm?id=341

 

[Chuck(G)]

When the IBM PC was first getting started, MIDI was very new and there were no MIDI adapters available for it. Some took the IBM async card and changed out the crystal on it and jumpered it for current-loop operation. It worked fine--MIDI is nothing more or less at the electrical level than serial comm over current loop.

 

[billdeg]

hmm hooking a teletype up to a midi keyboard? wonder if anyone has done this

 

[MikeS]

hmm hooking a teletype up to a midi keyboard? wonder if anyone has done this

Don't give Rory any more ideas!!!

Actually, since you'd probably only be transmitting, a PET MIDI controller would be pretty simple; just use one of the existing IEEE>RS232 interfaces, change the baud rate and add an opto-isolator for the interface.

One of my waiting-for-a-round-tuits projects is a MIDI interface for one of my Radio Shack M100s, to use it as a portable rhythm controller; looks pretty straightforward, especially since its UART can be programmed in software to be close enough to MIDI's 31250 baud.