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type: product
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stock_number: "95914-1"
canonical_url: "https://www.artisantg.com/95914-1/StarTech-PCI4S422DB9"
json_url: "https://www.artisantg.com/95914-1/StarTech-PCI4S422DB9.json"
generated_at: "2026-11-07T08:11:46.172Z"
last_updated: "2026-10-14T13:00:51.160-05:00"
---

# StarTech PCI4S422DB9 4-Port PCI RS422 RS485 Serial Adapter Card

_Summary and Categories are this item's record. The description sections and FAQ are machine-assisted and can contain errors; where they disagree with the record, the record is correct, and where description sections disagree with each other, Details wins._

## Summary

- Manufacturer: StarTech
- Model: PCI4S422DB9
- Condition: New From Surplus Stock
- Price: $115.00 USD
- Availability: In stock, 1 available
- Warranty: 1-Year Warranty with 30-Day Return Guarantee
- ITAR restricted: No
- Shipping weight: 1 lb, estimated
- Shipping dimensions: 8X8X3 in, estimated

## Categories

- Test Equipment > Electrical Test > Serial (primary)
- Military and Embedded Equipment > Embedded & Industrial > PCI

## Details

This unit is also known as Rayon Technology PCI4S422DB9 4-Port PCI RS422 RS485 Serial Adapter Card.

### Includes

- (4) DB9 to (1) DB37 Break-Out Cable
- (3) Rayon Driver Disks
- PCIPORT Card Owner's Manual

Part Number: 06051812

## Overview

This PCI expansion card provides four independent RS422/RS485 serial ports via DB9 connectors. It operates within a standard PCI slot, enabling full-duplex RS422 and configurable half/full-duplex RS485 communication, often with auto-direction control. Designed for industrial automation, data acquisition, and embedded control systems requiring robust, multi-point serial connectivity over extended distances.

## Function

Adds four high-speed, software-configurable RS-422/RS-485 serial ports to a host computer via a 32-bit, 3.3/5V PCI expansion slot. Each DB9 port is driven by a 16C550 UART with a 16-byte FIFO, supporting data rates up to 921.6 Kbps. Features include selectable 2-wire or 4-wire RS-485 modes with automatic transceiver control, enabling multi-drop communication for industrial automation, POS, and security systems.

## Platform

Compatible with PCI bus architecture supporting 32-bit 33MHz or 66MHz operation requiring available PCI expansion slot on desktop workstations servers or industrial computers running Windows Linux or Unix operating systems with kernel support for serial communication drivers and sufficient power delivery through PCI connector for multi-port serial interface operations in enterprise network infrastructure automation control systems or data acquisition environments.

## Application

Designed for use in industrial and embedded computing environments, this 4-port serial adapter card adds RS-422 and RS-485 serial communication interfaces via a PCI slot, enabling connection to multi-drop or point-to-point devices and networks. It supports flexible configuration of each port as RS-422 or RS-485, accommodates 2-wire and 4-wire RS-485 modes with automatic data direction control to simplify communication, and features a 32-byte transmit/receive buffer to reduce CPU load. Commonly applied in automation, process control, remote access, and industrial networking systems, it integrates into PCs requiring robust serial connectivity for device control and data acquisition.

## Accessories

Requires a host PC with available PCI expansion slot (motherboard, chassis). Interfaces include: 1x PCI bus edge connector (32-bit/120-pin or 64-bit/188-pin, 5V/3.3V keyed) for system integration; 4x DB9 male (9-pin D-sub) for RS422/RS485 serial communication with external devices. Operation requires compatible OS drivers and DB9 serial cables.

## Interface

Four DB9 serial ports supporting RS-422 and RS-485 communication standards. PCI (Peripheral Component Interconnect) edge connector for installation in standard PCI slots. Full-duplex transmission with data rates up to 921.6 Kbps. DB9 (9-pin) male connectors with 16C950 UART chipset. Requires 5V PCI slot in host computer.

## Images

- <https://www.artisantg.com/itemimages/startech_pci4s422db9_view1_2025827143257.jpg>
- <https://www.artisantg.com/itemimages/startech_pci4s422db9_view2_2025827143257.jpg>
- <https://www.artisantg.com/itemimages/startech_pci4s422db9_view3_2025827143257.jpg>
- <https://www.artisantg.com/itemimages/startech_pci4s422db9_view4_2025827143257.jpg>
- <https://www.artisantg.com/itemimages/startech_pci4s422db9_view5_2025827143257.jpg>
