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Green PCIe x1 card with four DB9 ports on a breakout cable

BFKK

BFKK 4-Port DB9 Serial PCIe x1 Card 115200bps

SKU CH-XKQK-DHZP8

Adds four DB9 serial ports via a PCIe x1 slot using an ASIX AX99100 chipset with 256-byte FIFO per port at up to 115200bps

  • PCIe 2.0 interface fits modern and legacy motherboards
  • Four DB9 ports add serial connectivity for industrial gear
  • AX99100 chipset supports 16C450 through 16C950 UART standards
  • 256-byte FIFO per port sustains 115200bps data rates
  • Windows and Linux drivers cover 32-bit and 64-bit systems

Four-Port Serial Expansion

This PCIe x1 card adds four DB9 RS232 ports through a single expansion slot using the ASIX AX99100 chipset. It complies with the PCI Express 2.0 specification and provides 256-byte FIFO buffers on each transmit and receive path. Each port supports data rates up to 115200bps with configurable 5-6-7-8-bit formats and one or two stop bits.

Industrial and Legacy Connectivity

The card suits engineers maintaining factory equipment, point-of-sale systems or scientific instruments that still rely on serial links. Full MODEM signal support including CTS, DSR, RI, DCD, DTR and RTS covers most legacy wiring schemes. Builders who need USB, Ethernet or fibre interfaces should look at other adapter types.

Headroom and Limits

Four independent ports handle multiple simultaneous terminals, modems or data loggers at the rated 115200bps each. The 256-byte FIFO depth helps sustain throughput under interrupt latency but does not eliminate the fundamental bandwidth ceiling of the RS232 standard. Systems requiring higher serial speeds or more than four ports will need additional cards.

Highlights

  • PCIe 2.0 interface fits modern and legacy motherboards
  • Four DB9 ports add serial connectivity for industrial gear
  • AX99100 chipset supports 16C450 through 16C950 UART standards
  • 256-byte FIFO per port sustains 115200bps data rates
  • Windows and Linux drivers cover 32-bit and 64-bit systems

Specifications

No published specifications for this item yet.

Questions about this item

Does this card need a free PCIe x1 slot on the motherboard?

Yes, the card plugs into a PCIe x1 slot that complies with the PCI Express 2.0 specification.

Can I keep my older serial devices that use 16C550 or 16C950 UARTs?

The ASIX AX99100 chipset supports 16C450, 16C550, 16C650, 16C750 and 16C950 UART standards, so those devices will work.

How do I confirm each of the four ports is running at 115200 bps after driver installation?

Open Device Manager, check the port properties for the configured baud rate, then run a loopback test or terminal session at 115200 bps on every port.

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