I’ve been quite busy with the 486 build. A while ago I decided to continue with the 486DX2-66 in favor of the 486DX-50. I added a CF card for a harddisk, I replaced the barrel battery with a CR3032 (which didn’t work, because the voltage probably is too low) and added a AA battery solution. I put in the Aztech sound card which was quite problematic to get to work. I still can’t get the LCD display to work, which is too bad.
Because I am spoiled with MIDI sound through the Roland MT-32 and SC-55, first with RetroPie and now with the MiSTer, I definitely wanted to add MIDI support to the 486. I found a relatively cheap option in the MDR-401 card from Midi System. This was much cheaper than the MPU-401 route and also than the PCMidi solution (which has long waiting times currently). Because there wasn’t much information available of the card, I was a bit apprehensive that it would not truly support intelligent mode. So I put it in and tried it with The Secret of Monkey Island (of course) and… it worked! Straight out the box (actually it was straight out of the envelope that damaged the pci bracket. I have never seen a bracket made from flexible plastic.)!
Because I now have two devices outputting MIDI signals: the MiSTer and the 486 (not counting the Amiga, which I hardly ever use for MIDI anyway), I have to rethink the wiring. The easiest solution is to use the second MIDI input on the front of the SC-55. I have to make the SC-55 the first device in the chain instead of the MT-32. And I probably need a longer MIDI cable. When I want to use the Amiga for MIDI or play on the MIDI keyboard, I can simply unplug the cable from the front of the SC-55.
Next steps for the 486 are making sure that the CD-ROM works and also the CD audio. Also, I want to look into the performance of the system.