It is better to have the box of the mpu-ipc rather than having the ISA interface: the whole Mpu chipset is inside the box making the ISA matching card just a simple interface to ISA .
For the ipc-t the chipset moved to ISA card and the box is just the ports more or less.
So in your case unless you find that Roland box the ISA card is nothing more than a few logic chips and thus not able to do any mpu work.

You can find a photo of the box electronics here: https://nerdlypleasures.blogspot.com/2013/06/ … intage.html?m=1

Hi keropi,
Can it be, that you mean MPU-401 and not MPU-IPC?
On my Card there are also the Roland Chips, like the MPU-IPC-T, See the picture.
Apparently it should suppose to be missing the hex inverter.
(Instead on the position of IC3 (74LS08) on my card, there is IC12 (74LS04, hex inverter) on the MPU-IPC-T)
This is the upper IC near the DSUB25 Connector.

Doa search for the wiring for the MCB-1 and and MPU-IPC. It might be possible to make an adapter for an MCB-1 to use it on the MPU-IPC.

I'll pull the cover off of my MCB-1 when I get home and take a gander at it to see if there is a hex inverter.

ah sorry I was thinking of the older model with the large breakout box...
I have no idea for this variant ...
maybe you can work out where pin12 goes and add the potential missing chip and test if this works (maybe you need to add a LS04 and the rest of the passives after that)