HP 9915A (industrial version of HP 85A)

From: roosmcd_at_dds.nl <(roosmcd_at_dds.nl)>
Date: Wed Oct 9 06:34:00 2002

 Hello,

 I also have a HP 9915A in my possesion. Useless without keyboard and I also
have only documentation for the HP-85.

> >There is also a little board inside that has eight sockets, four of which
> >are populated with 2732 eproms. I am wondering whether this is part of
> the
> >cpu system, or if it is for embedded program storage like the programmable
> >rom card for the 85.
>
> The later. There were software developement kits available that let you
> write programs in assembler and burn them into EPROMs that plugged into a
> HP-85 type plug-in cartridges (called a Hybrid ROM or something like that) or
> directly into the 9915. The EPROMs that are in it are probably Matrix and/or
> I/O ROM IIRC. That seems to be standard in the 9915s that I'm aware of.

 This sounds like they are absolute unobtainium today? I'd better start looking
for a HP-85, only they seem to want quite some money when I see them on
eBay :).
 
> FYI The 9915 doesn't use the HP-85 custom hybrid processor but uses an
> Intel CPU instead! However it does use the HP-85 keyboard processor but only
> for the timers that it contains.

 Are you sure? I must take a look at my machine then.. What kind of processor
is in there?

> >I presume that I can hook up a disk with an hp-ib card (and rom), so it
> >should be usable once I find a keyboard and appropriate monitor.
>
> Correct. With the keyboard and monitor it should act exactly like a HP-85
> (except your's doesn't have the tape drive). But it's a lot easier to find a
> HP 85, 86 or 87.

 I've always assumed you can't hook up a disk since there is are no disk
routines in ROM?

  greetings,
   Michiel
Received on Wed Oct 09 2002 - 06:34:00 BST