StarTech.com 4 Port RS232 RS422 RS485 PCIe Serial Card with 16C1050 UART

The StarTech.com PS74ADF-SERIAL-CARD is a highly versatile and robust PCI Express interface card, designed to add four external DB9 serial ports to your desktop PC. This card provides a simple and effective solution for connecting legacy industrial hardware, point-of-sale systems, and specialised equipment where modern interfaces are unavailable. It is ideal for integrating devices such as card readers, barcode scanners, label printers, and console management systems into contemporary computer setups.

A standout feature is the independent configurability of each port. Using the onboard DIP switches, you can select between RS232, RS422, or RS485 connections per port, offering immense flexibility for mixed-interface environments. Furthermore, each port supports configurable power delivery over pin 9 via an auxiliary SATA power connector, with options for 12V (1.5A per port), 5V (1.5A), or no power (RI), configured via dedicated jumpers. This makes it perfect for powering peripherals directly from the card.

Performance and Compatibility

Driven by the reliable Asix AX99100 chipset and a 16C1050 UART, the card ensures wide compatibility with legacy UART standards, including 16C450, 16C550, 16C650, 16C750, and 16C950. It delivers high-speed, bi-directional communication with a maximum baud rate of 921.6 Kb/s per port, supported by 256-byte FIFO buffers and COM port retention for stable data transfer. It supports multiple parity modes: Even, Odd, None, Space, and Mark.

Robust Protection and Installation

Built with durability in mind, the card features comprehensive ESD protection rated at ±8kV (Contact), ±15kV (Air), and ±15kV (HBM). For installation flexibility, it comes fitted with two standard-height brackets and includes an additional four low-profile brackets, making it compatible with both standard and small form factor desktop cases.

System Support

This serial adaptor card n