16c95x Serial Port Driver: !!install!!

Multi-port PCI/PCIe cards require the driver to properly map interrupts (IRQs) across 2, 4, or 8 discrete serial ports.

This decouples the driver from protocol handling, improving modularity.

Often appears in Device Manager under "Other Devices" with the Hardware ID OXPCIEMF\PNP0501 or OXPCI\VEN_1415 .

XR16C850/XR16C854/16C864/16C154/16C95x Universal Asynchronous Receiver Transmitter (UART) Datasheet

The 16C95x series is not a single chip but a family of high-performance UARTs. Key members include: 16c95x serial port driver

serial8250: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16C950/954 Use code with caution. Optimizing Linux Performance

The 16C95x’s 128-byte FIFOs drastically change the interrupt strategy compared to legacy UARTs.

If you have installed a multi-port serial card and are seeing a "PCI Serial Port" with a yellow exclamation mark in Device Manager, you need the . This article provides a comprehensive guide to identifying, downloading, installing, and troubleshooting this driver. What is the 16C95x Serial Port Driver?

The 16C95X utilizes an external clock crystal (often 14.7456 MHz or 18.432 MHz) to generate high baud rates. In the driver's advanced properties panel, look for a Clock Rate or Prescaler setting. Ensure this matches the hardware specification printed on your physical serial card. 3. Blue Screen of Death (BSOD) on Windows 10/11 Multi-port PCI/PCIe cards require the driver to properly

IRQ handler (outline)

Installing a dedicated 16C95X driver unlocks the following features:

Download the zipped driver files and extract them to a known location (e.g., Downloads).

Unlike the standard 16C550 which features a 16-byte FIFO (First-In, First-Out) buffer, the 16C95X family boasts a 128-byte deep FIFO buffer. This drastically reduces CPU overhead and prevents data loss at high speeds. If you have installed a multi-port serial card

Once installed, the ports will appear cleanly as Oxford PCI UART or 16C95X Serial Port (COMx) . For Linux Systems

if you need extreme low power or very simple 9600 bps-only systems (a basic 16550A suffices).

If characters are dropping or scrambed at high baud rates (115200 bps and above), the system is failing to clear the FIFO quickly enough.

The 16C95X serial port driver is a critical software layer required to unlock the high-speed, low-latency capabilities of industrial-grade UART chipsets. By ensuring the correct driver is installed, configuring the deep 128-byte FIFOs appropriately, and mitigating IRQ or latency conflicts, systems can achieve robust, uninterrupted serial communication even in high-demand environments.

Upon loading, the driver performs the following sequence: