Overview

Modems And RS-232

The cable that connects a standard modem to a computer device typically uses the wiring and signaling standard, "RS-232". The standard discusses the physical and electrical characteristics required for the interconnection.

There are a variety of configurations for an RS-232 cable as well as several common tools used to troubleshoot a problematic connection. This section of the Compendium discusses the RS-232 standard and several types of RS-232 interconnections as well as explaining how to use a Break-Out-Box to troubleshoot a cable problem.

Topics In This Discussion

• General Overview
• RS-232 Standard
• Bit Encoding
• Character Encoding
• Data Errors
• The RS-232 Physical Circuit
• DTE and DCE
• DB-25 Connection
• Control Signals
• Using a Break-Out Box
• Directional Signals