21 Apr
2006
21 Apr
'06
2:52 p.m.
I purchased an HP2397A color terminal. It needs a monitor and
keyboard. The monitor is straightforward and can be taken care of
with a cable. (Although it would be nice to find the appropriate HP
period monitor.) The keyboard is a different story. I need an HPIL
keyboard. Its my understanding that any HPIL keyboard would work, but
No you don't. HP never made an HPIL keyboard. The only HPIL keyboard that
I know about is the hack described in the book 'Control the World with
HPIL', to add a bigger keyboard to the HP71.
What uou need is an HP-HIL keyboard. Those are relatively common -- some
HP9000/200 and hP9000/300 series machines used them, as did the HP150-II
and the HP Integral. Along with some terminals, of course.
HPIL == Hewlett Packard Interface Loop
HP-HIL == Hewlett Packard Human Interface Link
that I'd need one that understands HPIL and
couldn't rig up a stock
PS2 style keyboard.
No, HP-HIL is very different to the PC keyboard interface. I do have some
information on HP-HIL -- enough to tell me I don't want to have to design
my own peripherals if I can avoid it. The HP keyboards contain a custom
HP-HIL slave chip, a COP400 series microcontroller, and a few 4000-series
CMOS chips to link to the key matrix.
From what I rememeber, there are various
'national' versions of the
standard HP-HIL keyboard. The differences are in
the keytops (not
suprisingly) and also in the fitting f up to 8 diodes inside which
determine the ID byte sent back by the keyboard. The system uses this to
work out what keyboard is connected, and thus what character code to
assign to each key. Your termninal should work correctly with any HP-HIL
keyboard.
No I don't think I have a spare one...
-tony