HP2748A papertape reader : connector ?

From: Bob Shannon <bshannon_at_tiac.net>
Date: Fri Jun 29 20:46:43 2001

This is interesting!

I have never seen a 2748 interfaced to a 8-bit duplex register board. This
would take a special cable, quite different from my reader cable.

The HP tape reader board I've always seen connected to the photo tape
readers is P/N 02116-8002. Its simply labelled "Tape Reader", and has
a two row of 11 DIP packages, 8 two-transistor data receivers, and a 7
transistor driver-receiver section for flag and control.

Because the HP processor has no need to send data to the reader, the more
complex and expensive 8 bit duplex register is overkill. But the signal levels
may be correct, if you have the right version of the duplex register board...

The HP Tape Reader 02116-8002 board can only send the state of the control
bit to the 2748 (or 2847) reader. It accepts 8 data bits on pins 1-4 and A-D,
which
is not compatible with the 8-bit duplex registers pin assignments.


Jay West wrote:

> The 2748A/B paper tape reader uses the "8-bit duplex register interface".
> That would lead me to believe it's an 8 bit interface, not a 16 bit one.
>
> I have full docs (& schematics I believe) for both the 2748B and the 8-bit
> duplex register interface board. I have two of those units presently
> running, so I can get the cable pinout too if you'd like (but I believe the
> cable diagram is in the interface manual). Let me know if you still need
> them.
>
> One word of caution about the facit 4070 punch... as I found out when I got
> mine - the facit had a board in it that was replaced depending on what
> electrical spec the system you were attaching it to used. I seem to recall
> that you had to specify which (of many) interfaces you wanted on the punch
> when you ordered it. So just because you find a 4070 punch doesn't mean it
> has the right board in it to hook up to the 8-bit duplex register board (hp
> punches and readers both used the 8-bit duplex register board). Matter of
> fact, unless it was found with an HP system, it probably DOESN'T have the
> right board for the HP. You can't tell from the outside either, as I've seen
> the RS-232 interface board in the punch presents a DB25 externally - just
> the same as the HP version of the card does (which is decidedly NOT RS-232).
>
> Jay West
>
> ----- Original Message -----
> From: Tony Duell <ard_at_p850ug1.demon.co.uk>
> To: <classiccmp_at_classiccmp.org>
> Sent: Friday, June 29, 2001 12:41 PM
> Subject: Re: HP2748A papertape reader : connector ?
>
> > >
> > > At 09:22 PM 6/28/01 +0200, you wrote:
> > >
> > > >A recent dumpster dive yielded a HP2748A papertape reader. Does anyone
> have
> > > >the interface spec's for this device handy ?
> > >
> > >
> > > I think *some* of HP's paper tape punches and readers use the
> 82032
> > > parallel interface. It's a 16 bit parallel interface with several
> >
> >
> > I suspect this is highly likely since the 16 bit parallel interfaces,
> > like the 82032, 98032 (for the 9825, etc) were used for many
> character-based
> > (and other) peripherals.
> >
> > > additional handshaking lines. Each data line can be set as Input only,
> >
> > I would be suprised if a paper tape reader used all the capabilities of
> > that interface, though. Most likely there are 8 outputs from the tape
> > reader (1 per data track), a data strobe signal (produced from the
> > sprocket track, and either an input signal to cause the reader to advance
> > one character (and read it) or one to start the tape moving, whereupon
> > you get data strobes every so many ms. Maybe signals for error (tape run
> > out, etc) and direction control
> >
> > There's not that much you need for a paper tape reader after all...
> >
> > > Output only or In and Out. I think have one around here somewhere that
> came
> > > off of a PT punch. You should have grabbed the PT punch, I think the
> Facit
> > > is what HP used or perhaps I should say one of the ones that they
> >
> > The Facit 4070 is what _everyone_ used :-). Yes, HP used it for a time
> > (one of the options for the 98032 is certainly to connect to a 4070, and
> > it was used with larger machines as well). So did Philips (on the P800
> > series). I've got a 3rd party card to link it to the DEC Unibus, and
> > information on a similar card for Omnibus. Oh, and my Fluke DVM system
> > has an option card to drive the 4070.
> >
> > I've even seen other paper tape punches (Trend made one based on the GNT
> > Model 34 mechanism) that have the same interface. The 4070 was almost a
> > de facto standard for paper tape punches.
> >
> > > used. What kind of connector is on your PT reader? I think most of
> the
> >
> > If its's the unit I'm thinking of, it's a connector similar to the ones
> > used for V.35 interfaces.
> >
> > -tony
> >
> >
Received on Fri Jun 29 2001 - 20:46:43 BST