UNIBUS/QBUS interface chips Was: Re: MEM11 update

[Brian Walenz]

I did a bit of searching in the fall for an 8881 (to fix a busted HALT
instruction on a PDP8a).  I concluded the 7439 is a pin-for-pin replacement
- I can't claim all credit for this, it's probably known by a few people
here.  My notes say the 8881 will handle 30mA loads.  The 7401 will handle
16mA, while the 7439 will handle 80mA.

Cheers!

b


On Mon, May 2, 2016 at 10:04 AM, Mattis Lind <mattislind at gmail.com> wrote:

> > The following chips have been used by DEC to interface to the QBUS, and
> > I have seen many of the above chips (e.g. 8641's) used there too, so I
> > think chips seen on one bus could be used on the other:
> >
> > Drivers:
> >
> > 7439 - Various - Quad NAND
> >
> > Transceivers:
> >
> > 2908 - AMD - Quad latching transceiver with tri-state output
> >
> > I _believe_ the following chips are also usable as UNIBUS/QBUS interface
> > chips, but I'm not sure if I've seen one used there:
> >
> > Transceivers:
> >
> > 8836 - National Semi - Quad NOR
> > 8838 - National Semi - Quad transceiver (aka Signetics N8T38)
> >
> > Quite a zoo!
> >
>
> DEC also used the DEC DC005 for the data and address lines on QBUS cards.
> The Signetics code is C2324N
>
> /Mattis
>
>
> >
> >         Noel
> >
>