Omnibus TSC8-75 schematic?

Rick Bensene rickb at
Fri Oct 30 09:04:50 CDT 2015

Eric Smith wrote:
> If a schematic isn't available, but a unit was made available on loan to
> reverse-engineer, I'd be willing to do it. 

At this stage, it appears that no original schematic for this board has been uncovered.

Efforts are currently underway to reverse-engineer an actual TSC8-75 board and derive a useful schematic. It is hopeful there will be something available relatively soon.  

The particular board being reverse-engineered has a serial number of <700, so it will not have the ESME IOT implemented, but it has been discovered that ETOS does not require this IOT in order to run properly.   ETOS will run slightly more efficiently if the board supports the ESME IOT (6365), but it will still run just fine on the boards that don't have the feature.

I'll try to post updates here as the project progresses.

It is my hope to be able to construct a functional equivalent of one of these boards, and get ETOS running on my physical 8/e system.   The biggest challenge is going to be replacing the pesky SP380A (12 used on the board) and SP314A (one used on the board) chips used for Omnibus interface, but there's a lot of discussion in the mailing list archives about replacements that seem to work , so it shouldn't be too difficult.


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