Opcode Studio 64X Not Recognized in OMS

[therealjho]

Hello all! I recently picked up a Macintosh Classic II with 10MB RAM. It’s in excellent condition and the capacitors were also replaced. I’m running Mac OS 7.5.3. I’m using a BlueSCSI external drive and a FloppyEMU floppy emulator.

The problem I’m trying to solve is that an Opcode Studio 64X MIDI interface won’t get recognized by OMS 2.3.3

The original OMS disks came with the interface and the OS is a fresh install. Serial ports on the Mac were tested with Snooper and passed. Serial cable is new. The interface receives and sends MIDI through the MIDI ports. I also tried to add the Studio 64X drivers manually in OMS Setup, but that didn’t work. I’m doubtful there’s a hardware issue due to the state of the interface (very clean, came in original box with original software) and the aforementioned functionality test for MIDI. I opened it up and it looked pristine, no obvious issues.

At this point I am stumped. Any ideas or suggestions out there? I greatly appreciate any help or insight from the community. Thanks!!!

[chrisNova777]

how many different serial cables do you have access to? i would say try a different serial cable (rs422)

https://www.8bitclassics.com/product/apple-8-pin-mini-din-serial-cable/

there are more than one type of mac serial cable. see this description :

Unfortunately, there are two types of serial cables commonly used with classic Macs.

-"Modem" cables are wired straight through,
-"printer" cables are wired as cross-over/null-modem,
with TX and RX swapped (so that TX on one end goes to RX on the other end, and vice versa).

Connecting two Macs back-to-back for LocalTalk requires the cross-over style cable.
I'd guess that's your issue - most of the modern Mini DIN-8 cables I've seen are wired straight through
https://68kmla.org/bb/index.php?threads/apple-talk-trouble.40692/

you may be using a "cross-over" cable (ie: mac printer cable) thinking its a serial cable, theres literally no way to tell by looking at the cable.. well maybe possibly by checking some of the text on the side of the cable but yea its easy to mistake the two, and swapping to the proper cable type will instantly solve the problem

male to male din-8 rs422 straight through (not crossover)

[therealjho]

Thanks for the advice! I just ordered the cable you provided from 8bitclassics.com

I’ll let you know if it works.

[therealjho]

@chrisNova777 you were right! I connected the MIDI interface to the Mac using a series of DuPont cables that mirrors the serial connector on the Mac and it showed up in OMS! As long as the cable I ordered is configured in the same way, I should be good. Thanks for your help! Much appreciated!!!

[chrisNova777]

i dont understand why the cables cant be marked to show the tx-rx wiring... but ya, cant fix something from the past..  in most cases theres no way to tell the cord wil either work or it wont work. if it doesnt detect its probably the wrong type of cable. these cables are getting harder and harder to find too.

local talk cable was for transferring files from one mac to another with a direct 1-cable connection between the two..  (in pc world this is called null-modem laplink cable)

[therealjho]

Just circling back to close the loop. The serial cable from 8bitclassics works perfectly!! Thanks again for your guidance and knowledge. Much appreciated!!