Description
IBM 6320947 Parallel Serial Adapter Card ISA 8-Bit DB25 DB9 RS-232 1984
The IBM 6320947 is an 8-bit ISA expansion card that provides both a parallel port (DB25) and a serial RS-232 port (DB9) for IBM PC, PC/XT, and PC/AT-class computers. The card carries the board designation "COMP SERIAL / PARALLEL" and is dated September 30, 1984, placing it squarely in the early IBM PC era. It populates one ISA slot and exposes its bracket connectors — a standard 25-pin parallel port above a 9-pin serial port — for connecting printers, plotters, modems, and other RS-232 peripherals.
Specifications & What's Included
- Manufacturer: IBM
- Part Number: 6320947
- Bus Interface: ISA 8-bit (62-pin edge connector)
- Parallel Port: DB25 (25-pin female), standard Centronics-compatible
- Serial Port: DB9 (9-pin male), RS-232
- Oscillator: CTS Singapore MXO-55GR-40, 1.8432 MHz (standard UART baud-rate crystal)
- Logic ICs: Texas Instruments SN74LS-series and SN75-series TTL logic
- PCB date code: September 30, 1984
- Form factor: Half-length ISA card with full-height bracket
- Included: Card only — no cables
Applications
Parallel/serial combo adapter cards like the IBM 6320947 were standard expansion hardware in the early-to-mid 1980s IBM PC ecosystem. Early IBM PCs and XTs shipped with minimal or no built-in I/O, so a card like this was required to connect a dot-matrix or daisy-wheel printer via the parallel port and a modem, mouse, or terminal via the serial RS-232 port. The 1.8432 MHz baud-rate oscillator is the classic frequency used to generate standard baud rates (300, 1200, 9600 bps and higher) via the UART divider chain. Today these cards are sought by vintage PC restorers and hobbyists maintaining original IBM PC, PC/XT, and early PC/AT systems, as well as by industrial users keeping legacy 8-bit ISA-bus equipment operational.
This IBM 6320947 Parallel Serial Adapter ISA card has been inspected and appears to be in good used condition. The PCB shows normal handling and shelf wear consistent with its age — light oxidation on the gold ISA edge connector fingers and minor dust, but no visible cracks, broken traces, or missing components. Both the DB25 parallel port and DB9 serial port bracket connectors are intact. The board dates to September 1984. It has not been powered up or tested at our facility, but it was pulled from a working environment where it was previously in use. Please view our photo set and contact us if you have any questions.
Warranty Information
Additional Information
Brand: |
IBM |
Model: |
6320947 |
MPN: |
6320947 |
Type: |
Parallel/Serial Adapter Card |
SKU: |
40951 |
Interface: |
ISA 8-Bit |
Bus Type: |
ISA (8-bit) |
Serial Interface: |
RS-232, DB9 (9-pin) |
Parallel Interface: |
DB25 (25-pin) |
Number of Ports: |
2 (1 parallel DB25, 1 serial DB9) |
Connector Type: |
DB25 (parallel), DB9 (serial) |
Form Factor: |
Half-Length ISA Card |
Compatible With: |
IBM PC, IBM PC/XT, IBM PC/AT, ISA-bus systems |
Manufacture Date: |
September 30, 1984 |
Country/Region of Manufacture: |
Malaysia / Singapore (per board markings) |
Seller Notes: |
Card only; no cables included. |
Condition Notes: |
This IBM 6320947 Parallel Serial Adapter ISA card is in good used condition with normal shelf and age-related wear. Not tested at our facility but pulled from a working environment. Both DB25 and DB9 connectors are intact. |
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 |