Michael, here's an excerpt from a posting to comp.sys.hp.hardware (Nov 96)
by Bill Hassell that gives the pin-out I think you need:

    The large Centronics-like connector is an HP proprietary connector
    that was designed to use a number of different interfaces, and by
    using a different cable, access other serial connections.  I have
    never seen an HP terminal with an HPIB connector.

    There are several versions of the cables, but for do-it-yourself
    cables, there are just 2...modem and direct connect.  The direct
    connect cable would plug into a DTE computer port directly while
    the modem cable goes directly into a modem.

    Be aware that terminals of that vintage (early to mid 1980's) were
    designed for use with HP 3000 and HP 1000 computers where pacing was
    much more complex, using both ENQ/ACK to handle data flow and
    DC1/DC2 for block mode operation.  This connector even has clock
    signals (16x) where you can supply the clocking speed and literally
    change the baud rates on the fly with no loss in data.  You'll need
    a manual for complete info.

    Here's the pinouts (the RS-232 column is the 25 pin connector, the
    DIRECT column list the pin on the terminal side to use for a direct
    connect, while the MODEM column lists the pin on the terminal
    connector to use for a modem connection:

    SIGNAL RS-232  DIRECT  MODEM
    ------ ------  ------  -----
    shield    1      nc     nc
    DataOut   2      42     12
    DataIn    3      12     42
      CA      4             13
      CB      5             44
      CC      6             45
     gnd      7      48     48
      CF      8             46
     SCA     11             15
     SCF     12             27
      DB     15             41
      DD     17             43
      CD     20             14
      CE     22              9
      CH     23             40
      DA     24              7


-----Original Message-----
From: Michael L Gueterman [mailto:[log in to unmask]]
Sent: Tuesday, March 21, 2000 10:47 AM
To: [log in to unmask]
Subject: HP2627A Datacomm Connection


  I just picked up an old HP2627A terminal, and although I remembered
that it had an odd connector (50 pin centronics style), I had hoped I
could hook it up to my 935 as a console (what the heck :)  Does anyone
happen to have any idea of the pinout I would need to make a cable
for it?  I had thought that it was a serial interface, but it's been
close to 20 years since I last messed with one of these.  If I'm
wrong, I guess Lee gets another piece of HP memorabilia for the
Computer History Museum :)

Regards,
Michael L Gueterman
Easy Does It Technologies
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