While MIDI is a fairly simple protocol, it has unique requirements for the physical layer. Because it was designed to be used as part of a larger system, which might be on stage with hundreds of other cables carrying line voltage, amplified signals, and all sorts of issues with grounding, MIDI is supposed to be isolated. This means the receiving end of a MIDI cable should have an optocoupler or other isolation barrier to prevent damage to the equipment, no matter what is happening to the cable. Getting this right is often overlooked, but now you can drop the MIDI CHIP, a MIDI-compliant module, into any project and immediately get bi-directional, isolated MIDI connections.
The MIDI CHIP is a nice, simple design that offers 5300Vrms isolation and comes as a pair, so you’ve got one for both ends of a connection! It is breadboard compatible, using standard 0.1″ headers spaced appropriately. But it can also be used directly, soldered or glued into just about anywhere with its tiny 0.7″ x 0.85″ (~1.8cm x 2.15cm) footprint.
A simple jumper can switch it to a buffered MIDI Thru, which is a nice feature as it adds isolation to an existing connection. It can also operate at either 3.3 or 5V, again depending on a solder jumper. This allows it to interface with just about any popular microcontroller platform! It’s a perfect match for the Arduino MIDI Library. Seeing as how MIDI is essentially just a serial stream at 31250 baud, it’s easy to interface with the UART portion of a microcontroller, so building custom controllers or MIDI sniffers with these boards is a snap.
If you’re into synths, chiptunes, or just MIDI control in general, the MIDI CHIP is bound to find a use in one of your projects. As mentioned before, you get a pair for the price, which is a great deal! If you want built-in MIDI connectors, check out the MIDI CHIP Pro from the same seller, a complete MIDI module ready to be added to any project!
