MIDI

Tags: protocol, connector, music technology

MIDI is a protocol used to transmit data about musical events.


Physical

A MIDI connector uses three pins: ground, +5V, and a data sink. It can be used over five-pin DIN, TRS, TS, or purely digitally. Although not standardised for a long while, manufacturers have used MIDI over TRS (most commonly 3.5mm) for a long time. There are three TRS variants.

Pin function DIN connector pin1 TRS A (standard) TRS B TS / TRS C
Data (current sink) 5 Tip Ring Tip
+5V (current source) 4 Ring Tip Sleeve
Ground 2 Sleeve Sleeve None

Gallery

A MIDI DIN connector, front view of a top connector.
Image by Fred the Oyster.
License: CC-BY-SA.
A MIDI DIN connector, front view of a top connector.
Image by Fred the Oyster.
License: CC-BY-SA.
A MIDI DIN connector, front view of a top connector.
Image by Fred the Oyster.
License: CC-BY-SA.
A MIDI DIN connector, front view of a top connector.
Image by Fred the Oyster.
License: CC-BY-SA.

Footnotes

  1. DIN connector does not use pin 1 or 5. Whack! 


Further reading