Description
Computer Boards Inc. 8-Bit ISA 36-Pin Serial Card CP82C65A 8255 PPI Rev 2 1990
This is a vintage 1990 8-bit ISA expansion card from Computer Boards, Inc. (CBI), built around the CP82C65A-5 — a CMOS implementation of the Intel 8255A Programmable Peripheral Interface (PPI). The card provides three independently configurable 8-bit I/O ports (Port A, Port B, Port C) accessible via the 36-pin D-sub connector on the bracket. Base address is set via a red DIP switch bank labeled "ADDRESS" on the PCB. The board is marked Rev. 2, dated 1990, and manufactured in the USA.
Specifications & What's Included
- Manufacturer: Computer Boards, Inc. (CBI)
- Bus Interface: 8-bit ISA
- Main Controller: CP82C65A-5 (CMOS 8255A Programmable Peripheral Interface)
- I/O Ports: 3 × 8-bit programmable ports — Port A, Port B, Port C
- Bracket Connector: 36-pin D-sub female
- Address Configuration: DIP switch bank (labeled ADDRESS on PCB)
- Additional header: Base/Port/Control/Wait State jumper header on PCB
- Support ICs: Several 74LS-series logic ICs (74LS138, 74LS33N, and others)
- PCB Revision: Rev. 2
- PCB Flammability Rating: 94V-0
- Year Manufactured: 1990
- Country of Origin: Made in U.S.A.
- Includes: Card only — no cables
Applications
The Intel 8255A Programmable Peripheral Interface was one of the most widely used parallel I/O controllers of the 1980s and early 1990s, and cards like this one brought that capability to the IBM PC/XT and AT-compatible ISA bus. The 8255A's three independently programmable 8-bit ports made it well suited for interfacing PCs to external hardware — data acquisition systems, relay control boards, industrial I/O racks, stepper motor controllers, and custom instrumentation. Computer Boards, Inc. was an early specialist in PC-based data acquisition and I/O, producing ISA cards aimed at test, measurement, and industrial automation applications before the company became part of Measurement Computing. Cards of this type were commonly used in laboratory automation, manufacturing process control, and engineering test stands during the PC/XT and AT era of the late 1980s through the mid-1990s. Today they remain relevant to legacy system maintenance, vintage computing enthusiasts, and anyone who still runs 8-bit ISA-based control hardware.
This Computer Boards Inc. 8-Bit ISA Serial Card (CP82C65A 8255 PPI, Rev 2) has been inspected and appears to be in good used condition. The PCB looks clean with no visible cracks, burns, or broken traces. The 36-pin D-sub connector and ISA edge fingers look intact. There is light handling wear typical of a card from 1990, but nothing that stands out as a concern. Please review all photos and contact us with any questions.
Warranty Information
Additional Information
Brand: |
Computer Boards, Inc. |
Model: |
94V-0 Rev 2 |
MPN: |
2592 |
Type: |
8-Bit ISA Serial / Parallel Interface Card |
SKU: |
42952 |
Chipset: |
CP82C65A-5 (CMOS 8255A Programmable Peripheral Interface) |
Bus Interface: |
8-Bit ISA |
Connector Type: |
36-Pin D-Sub Female (bracket-mounted) |
Number of Ports: |
3 (Port A, Port B, Port C) |
I/O Configuration: |
8255A PPI – 3x 8-bit programmable I/O ports |
Address Selection: |
DIP switch (labeled ADDRESS on PCB) |
PCB Revision: |
Rev. 2 |
Year Manufactured: |
1990 |
Country/Region of Manufacture: |
United States |
Form Factor: |
Half-Length ISA Expansion Card |
Compatible With: |
IBM PC/XT, AT, and compatible 8-bit ISA systems |
PCB Rating: |
94V-0 |
Seller Notes: |
Card only; no cables or brackets included beyond what is shown in photos. |
Condition Notes: |
This Computer Boards Inc. 8-Bit ISA Serial Card (CP82C65A 8255 PPI, Rev 2) has been inspected and appears to be in good used condition. PCB is clean; ISA edge connector and 36-pin D-sub look intact. Light age-related wear. |
California Prop 65 Warning: |
WARNING: This product can expose you to chemicals including lead and lead compounds, and DEHP (a phthalate), which are known to the State of California to cause cancer and birth defects or other reproductive harm. Go to P65Warnings.ca.gov |