PCI Express 8-Port RS-232/422/485 Serial Interface

Product Announcement from Sealevel Systems, Inc.

PCI Express 8-Port RS-232/422/485 Serial Interface-Image


  • Eight serial ports each individually configurable for RS-232, RS-422, or RS-485
  • 16C954 buffered UARTs with 128-byte FIFOs
  • Supports 9-bit protocol framing
  • Oscillator and clock prescalar support wide range of baud rates
  • Each port supports data rates to 921.6K bps
  • RS-485 line termination, pull-up and pull-down resistors for each port are selectable via dipswitch
  • RS-485 ECHO can be enabled/disabled via dipswitch
  • PCI Express X1 compliant
  • Compatible with all standard size PCI Express slots
  • All modem control signals implemented in RS-232 mode
  • Automatic RS-485 enable/disable in hardware

Sealevel Systems, Inc. introduces the new Ultra COMM+8.PCIE serial interface, which delivers the ultimate flexibility for expanding serial communications in a variety of test and measurement, process control, and point-of-sale applications.Compatible with any PCI Express slot, the board provides eight multifunction serial ports, each individually field-configurable for RS-232, RS-422, or RS-485. The Ultra COMM+8.PCIE utilizes 16C954 UARTs with 128-byte Tx/Rx FIFOs which enables data rates to 921.6K bps for reliable high-speed communications in data intensive applications. This high-performance UART includes 9-bit framing support and is register compatible with legacy 16550 software applications. In addition, the board derives a 62.5 MHz clock from the PCI Express bus. This ultra high-speed clock is divided by a flexible 16-bit clock prescalar to provide support for the widest range of standard and non-standard baud rates.

In RS-485 mode, the board provides automatic control of the RS-485 driver in hardware, eliminating the need for application software control. This allows the Ultra COMM+8.PCIE to be used with standard serial communications applications and removes the risk of bus contention and data corruption. Additionally, RS-485 network termination, critical to robust multi-drop communication, can be selectively added to the circuit via DIP-switches. In RS-232 mode, all modem control signals are implemented for maximum compatibility with a variety of serial peripherals.

Sealevel SeaCOM software driver and utilities make installation and operation easy using Microsoft Windows and Linux operating systems. The Ultra COMM+8.PCIE (Item# 7804e) ships with a 36-inch cable that terminates to eight DB9M connectors.