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ComputerGeek
April 27th, 2018, 10:25 PM
Is there any way to use an imsai 8080 minicomputer in the same way as a fairlight cmi? Is there some type of midi interface for a (piano not typing) keyboard? Maybe an audio board?

Ragnarock
April 28th, 2018, 02:42 PM
MIDI can be done through a normal UART and programmed just like talking to a terminal. The baud rate is 31.250 which is high for an old system and might require special clock. Beyond that, circuits are easily found that take the TTL output from the UART and drive a MIDI connector, and the input would use a 4N38 optocoupler. Typical RS232 drivers are not used and would simply be bypassed (1488,1489).

Corey986
April 28th, 2018, 04:29 PM
Is there any way to use an imsai 8080 minicomputer in the same way as a fairlight cmi? Is there some type of midi interface for a (piano not typing) keyboard? Maybe an audio board?

Nothing is going to be like a fairlight except a fairlight. If you are simply looking to use an s100 system for sequencing, then their maybe a midi solution. But except for big bucks back in the day like the fairlight and synclavier you had stuff that sounded like 8 bit video games.

I will be demo’ing at VCF east the PT three voice Sound System on my Sol-20. The music system does have a sequencer but it is nothing like the fairlight (I owned a Fairlight series II eventually upgraded to a III when they were new so I know)

glitch
April 28th, 2018, 05:36 PM
Someone's got videos online of playing Fairlight samples through a R-2R DAC with an IMSAI, I remember watching it but I don't remember the details. They seem to be using the Model 6 music board:

https://www.youtube.com/watch?v=gs264O-UpNs

commodorejohn
April 28th, 2018, 10:19 PM
Yeah, the Fairlight is considerably more than just a single-channel DAC setup - it's eight-voice polyphonic in hardware. That said, if people can get 4-channel tracker playback on an Apple II with nothing but a 1-bit software-driven speaker output, it's probably possible to do something reasonably useful with a 2-4 MHz Z80 and a DAC.