When Randy, at Timewave, bought the AEA product line of TNCs and Multi-mode controllers in 1996, he only got the AEA documentation, tooling and boards for current or recent products.http://www.geocities.jp/tnc_gallery/pcb88-e.htm
The PCB-88 is an ISA COM (Serial board: bus interface, 16450 UART) with the PK-87/PK-88 era TNC on the same ISA card.
So proper setup means setting the IRQ and hardware port (COM1-COM4) ... that is important with newer motherboards that have built-in COM ports and IRQ dedicated for specific hardware devices (mouse, keyboard, parallel port, etc.).
Lyle Johnson, TAPR did add the 9600 baud card to the PCB-88 in 1992.
He mentions 26-pin header and TAPR TNC-2 similarities.http://www.ka9q.net/psr-48.pdf
AEA made this ISA card, as well as an earlier PK-90 and PK-89 external TNC that has marginal to non existent documentation. What does exists on Internet comes from former AEA customer support or employees.http://www.tapr.org/pipermail/aprssig/2005-December/011332.html
For example: Bob Donnell, KD7NM worked in AEA's Customer Support Group from 1990 until March 1994 and provided the AEA PK-90 information that you will find on Internet or support forums today.http://www.tapr.org/pipermail/aprssig/2005-December/011304.htmlThe AEA PK-90 is a commercial TNC version of the amateur radio AEA PK-87 TNC.
Rick, W4PC at CSS had this basic information (to operate software):
Switches 1-4 provide the base address (hardware) for the COM port when turned on
SW-1 $03f8 COM1:
SW-2 $02f8 COM2:
SW-3 $03e8 COM3:
SW-4 $02e8 COM4:
Switches 5-8 provide the IRQ when turned on
PkTerm '99 does work with the PCB-88 and
allowed you to run the TNC under Windows 95/98/Me and Windows NT/2000.