Description

What is it?

A simple RS-232 to MIDI adapter was thrown together so you can have some way of of plugging a MIDI-cable into my Commodore Amiga 500 though it should also work with 500+/600/1200/2000/3000/4000. This adapter is meant so that you’d have some way of connecting your favourite MIDI-device to your favourite Commodore Amiga computer (as long as it one of the more common variants and within reason).

Why did you make it?

Up until a few years ago, if you needed an Midi cartridge for your Amiga you’d usually ask on a forum and quickly get a response from somebody either willing to sell theirs for some small amount, or even send one to you for free. But something’s happened to Amiga hardware in recent years…second-hand prices have exploded, parts have become more scarce, and it’s getting harder and harder for those of us who still produce Amiga music

What makes it special?

Commodore Amiga computers never came with MIDI-ports built into it, this adapter plugs into the serial port of your Commodore Amiga 500/600/1200/2000/3000/4000, adding the ports you never knew you wanted. This version of the adapter has an IDC-plug on it, allowing it to be used with a 26-pin IDC to female DB25 cable

BOM:

• 9x 100nF ceramic capacitor (5mm) C1-C9
• 1x 1N4148N small signal diode (DO-35) D1
• 1x 2×13 pin straight IDC socket J1
• 2x Female S-terminal 5pin DIN PCB J2-J3
• 1x 2k2 (2200) ohm resistor R1
• 3x 220 ohm resistor R2, R3 and R4
• 1x 6N138 opto-coupler (DIP-8) U1
• 1x 7805 (TO-220) U2
• 1x 74HCT00 (DIP-14) U3
• 1x MAX232A (DIP-16) U4

Important notes:

• This includes only the PCB, no components or 3D print housing.
• When connecting or removing the sampler to the Amiga ENSURE THE AMIGA IS TURNED OFF! Old machines like these are quite sensitive to this and, given the age of the internals of the computer, probably more so these days!
• Picture with components on is only for illustration purpose.