Hi Bob,

> >>> Now if only IBM had kept all the input pins on the printer ports the same
> >>> polarity, I'd be walking on Cloud 9. Wake me up when the ride is over!
> >>
> >> They wanted certain levels on the port after a hardware reset,
>
> Actually I was talking about the input pins. BUSY is inverted in relation to
> PE, SELECT, ACK, and INIT.

Quite, but I think the same reasoning holds here.  I expect that in
the default mode, like with a happy idle printer plugged in and
idle you readback a 0 or something.  Or perhaps if you write
a 00 to the control pins the printer will respond with a zero.
It might be usefull to just check the BIOS code of an XT to see
what the test the port and test for printer conditions were,
there will have been some method in the madness but I agree
these days that a 16 bit IO port would be a lot more use,
not going to happen though.  USB and Firewire will make it
all moot for the end user and the developer (us PIC guys) will just
have to put up with it.

Cheers     *<<<-|
--
Kalle Pihlajasaari   kalle@ip.co.za   http://www.ip.co.za/ip
Interface Products   P O Box 15775, DOORNFONTEIN, 2028, South Africa
+ 27 (11) 402-7750   Fax: 402-7751    http://www.ip.co.za/people/kalle