HP board id?

[Paul Birkel]

Very interesting.  What do they recommend on the receiver-end?

Is the "HP 1000 M/E/F-Series Computers I/O Interfacing Guide" (02109-90006
September 1980) available online somewhere?

On Wed, May 13, 2015 at 11:20 PM, J. David Bryan <jdbryan at acm.org> wrote:

> On Wednesday, May 13, 2015 at 19:40, Marc Verdiell wrote:
>
> > ...where to get the older CTuL logic IC bus drivers (the 9956 in
> > particular) besides from old boards?
>
> With the inclusion of a pulldown resistor to -2V, the TI SN75121 is a
> recommended replacement, per page 5-6 of the "HP 1000 M/E/F-Series
> Computers I/O Interfacing Guide" (02109-90006 September 1980).  It's an
> active part:
>
>   http://www.ti.com/product/sn75121
>
>                                       -- Dave
>
>