User`s manual

Introduction

Overview

The CyberResearch COMHP 7804 is an eight channel RS-232/485/422 PCI Bus serial I/O adapter supporting

data rates up to 921.6Kbps.

The RS-232 compatibility allows for connection to devices utilizing the RS-232 electrical interface, such as

modems, data-entry terminals, and plotters.

RS-422 provides excellent communications for long distance device connections up to 4000ft., where noise

immunity and high data integrity are essential.

RS-485 is optimized for ‘Multi-Drop’ or ‘Party-line’ operations selecting data from multiple peripherals (as many as

31 devices can be connected on an RS-485 bus).

In both RS-485 and RS-422 modes, the card works seamlessly with the standard operating system serial driver. In

RS-485 mode, our special auto-enable feature allows the RS-485 ports to be viewed by the operating system as a

COM: port. This allows the standard COM: driver to be utilized for RS-485 communications. Our on-board

hardware automatically handles the RS-485 driver enable.

The COMHP 7804 also features Universal Bus (3.3 and 5.0V) operation.

What is Included

The COMHP 7804 is shipped with the following items. If any of these items is missing or damaged,

contact CyberResearch.

• COMHP 7804 Serial I/O Adapter

• Software CD

COMHP 7804 CyberResearch

Serial Communication