StarTech PEX2S953 2-Port PCI Express RS232 Serial Adapter Card with 16950 UART

The StarTech PEX2S953 is a high-performance 2-port PCI Express RS232 serial adapter card designed to provide reliable connectivity for legacy serial devices. Utilizing the Asix AX99100 chipset and advanced 16950 UART technology, this internal expansion card allows you to add two DB9 serial ports to your computer via a PCIe slot. It is engineered to handle demanding data transmission tasks with high efficiency, supporting baud rates up to 921.6 Kbit/s and featuring a 256-byte FIFO buffer to prevent data loss during high-speed operations.

Advantages

This adapter card offers exceptional compatibility and performance for professional and industrial environments. By providing native-like serial port functionality, it ensures seamless interaction with a wide range of peripheral equipment. The inclusion of both full-profile and low-profile brackets makes it highly versatile for installation in various computer case form factors. Furthermore, the ability to provide 5V or 12V power output on Pin 9 when connected to an external power source adds significant flexibility for powering specific serial devices directly through the interface.

Suitable for

• Connecting legacy serial devices such as barcode scanners and card readers
• Interfacing with industrial equipment like CNC machines and PLCs
• Managing serial-based communication for printers and modems
• Integration into POS systems requiring reliable serial connectivity

When it may not be suitable

This card is designed specifically for systems with available PCI Express slots and is not compatible with older PCI or legacy expansion slots. It is also not intended for use in devices that do not support standard Windows or Linux operating systems.

Key specifications

• Host interface: PCI Express
• Ports: 2 x RS232 DB9 serial ports
• UART: 16950 compatible
• Maximum baud rate: 921.6 Kbit/s
• FIFO buffer: 256-byte depth per port
• Chipset: Asix AX99100
• Power output: 5V/12V on Pin 9 (with external power)
• Form factor: Includes low and full-profile brackets

How to use

To install the card, power down your computer and disconnect the power supply. Open the computer case and insert the card into an available PCIe slot, securing it with the appropriate bracket for your chassis. Once installed, reconnect the power and boot your operating system. The system should automatically detect the hardware, though you may need to install the latest drivers from the manufacturer's website to ensure optimal performance and full feature access. Once configured, connect your serial devices to the DB9 ports on the back of the card.

What to consider before purchase

• Verify that your computer has an available PCIe slot
• Check if your serial devices require 5V or 12V power via Pin 9
• Ensure your operating system is supported by the current driver set
• Confirm the physical space inside your computer case for either low or full-profile installation

Usage recommendations

For the best performance and stability, ensure that the card is seated firmly in the PCIe slot and that all drivers are updated to the latest version provided by the manufacturer. If your serial devices require additional power, ensure a stable external power source is connected to the card to utilize the Pin 9 power output feature.