MASSBUS disk emulator (Was: Unibus controller for MFM disks)

Josh Dersch derschjo at
Tue Oct 18 11:05:22 CDT 2016

On 10/18/16 6:39 AM, Noel Chiappa wrote:

>      > From: Paul Birkel
>      > Maaaaaybe there are three ribbon cables back there
> Sure looks like it, and running to a standard MASSBUS connector, to boot.
> (Not that I have any use for the latter - absolutely no MASSBUS cables at
> all. But one could just run flat cables from this, to one's RH11/RH70.)
> I don't see a second MASSBUS connector, wonder what they do about
> termination? Maybe it's onboard? So I guess one could only have one
> of these things per MASSBUS port? Not really a problem, of course! ;-)
I can shed a bit of light here.  There are two components involved. On 
the emulation end, there is a PCI card with an FPGA that implements the 
interface logic; and there is software on a PC that deals with device 
logic and storage.  Between the PC and the MASSBUS interface on the host 
machine, there is a driver/receiver board that adapts signal levels 
between MASSBUS and the FPGA.

> We _definitely_ need to put these things in 'production'.


- Josh

> 	Noel

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