MIDI, the Musical Instrument Digital Interface, was conceived in 1981 and appeared in synthesizers and drum machines in 1983.
It was a means of connecting synthesizers and other musical instruments using a vendor-agnostic connector/cable and digital information protocol. It allowed a musician to connect his Yamaha keyboard to his Roland drum machine and play them both at the same time.
MIDI also allowed specialized computers, called sequencers, to talk to any synthesizer or instrument with a MIDI interface.
MIDI revolutionized electronic music. It allowed musicians to connect many instruments together and play individual parts on each, to layer instruments and to record and write music digitally, in a way that they could then go back and edit.
In live performance, MIDI made all kinds of performances possible with just a few musicians. New Order and the Pet Shop Boys, for instance, relied heavily on MIDI-based synthesizers to compose and reliably perform their music.
MIDI also made it to the computer. MIDI interfaces were made for the Apple II, Atari 8 bit computers, Commodore 64/128, IBM, Radio Shack Color Computer and, most notably, the Atari ST series. The Atari STs were the computer to own if you wanted to to do sequencing in the late 80s and early 90s.
Obviously, there was no commercial MIDI interface for the Timex/Sinclair computers. As a hardware device, MIDI was reasonably easy to implement. The Motorola 6850 ACIA, used in the Atari 520 ST, makes an excellent CPU-to-MIDI interface when fed the right source clock.
Building a MIDI interface for the Timex/Sinclair
In a series of articles, Lou Champagne documented how to interface the 6850 to a Timex/Sinclair 1000 or 2068, thus giving either computer the ability to drive synthesizers, drum machines and other MIDI instruments.
Lou’s interface is clever and minimal, but due to the limitations of Sinclair BASIC on the TS 1000, requires machine code to read/write from the ACIA. He wrote about MIDI messaging and some of his test code in the second article.
Making music with the Timex/Sinclair
Richard Hurd was one enthusiast who used MIDI with his Timex/Sinclair 2068 to play and record music.
Richard used a MIDI interface for the Spectrum, which he used with a twister board and Spectrum ROM, to play music on his 2068.
Hurd later built Champagne’s MIDI interface for his 2068 and wrote his own sequencer to play and record music using his 2068.
Just another way TS enthusiasts pushed their computers to and beyond their limitations, well past the expiration date.
