Xebec made a number of "specialized" bridge controllers, which fit between
the host adapter, which is what you've described, in this case possibly
intended to go to a compatible version of their 14xx-series controllers
which, in turn, provides a SCSI interface to an ST506 drive, which you
apparently have on hand.
It is likely that the 26-pin connector is to the Apple II version of SCSI
which was put out back then on a 25-pin DB-25 connector.
I recently got a drive with a Xebec label on its enclosure, having bought it
for the enclosure, and found the drive had an integrated adapter on it which
was terninated in a DC-37 connector, not unlike what was on the early
Bernoulli Boxes from IOMEGA. I didn't investigate the pinout or anything,
naturally, since I don't care about small drives like this. There's
probably a similar version for this card's interface as well.
Dick
-----Original Message-----
From: Pete Turnbull <pete_at_dunnington.u-net.com>
To: Discussion re-collecting of classic computers
<classiccmp_at_u.washington.edu>
Date: Saturday, April 17, 1999 9:45 AM
Subject: Apple HAL XEBEC controller
>One of today's acquisitions is a small card for an Apple ][ (or Apple ///),
>labelled "APPLE 2/3 XEBEC INTERFACE REV 1".
>
>I happen to have a couple of old Xebec ST412 winchester controllers, so I'd
>like to try this out.
>
>Can anyone tell me the pinout of the 26-pin header at the end of the card?
> Pins 3,7,11,15,17,19,21,23,25 are grounded, the other seventeen seem to be
>signal lines. Pins 1,5,9,13,20 are high impedance; the other even-numbered
>pins are terminated by a 220/330R resistor pack.
>
>Does it need any other software (like a formatting disk)? The on-board 4K
>EPROM contains only the strings "(C) HAL COMPUTERS LTD 1983", "A/XHAL
>SHARED RESOURCE WINCHESTER SYSTEM", "NOT CONNECTED", and "SRS ERROR", so I
>guess there would have been a floppy with it, originally.
>
>--
>
>Pete Peter Turnbull
> Dept. of Computer Science
> University of York
Received on Sat Apr 17 1999 - 13:26:28 BST