Black Box IC266A manual Appendix C Asynchronous Communications

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APPENDIX C: Asynchronous Communications

Figure C-1. Asynchronous communications bit diagram.

This special bit is called the parity bit. Parity is a simple method of determining if a data bit has been lost or corrupted during transmission. There are several methods for implementing a parity check to guard against data corruption. Common methods are called (E)ven Parity or (O)dd Parity. Sometimes parity is not used to detect errors on the data stream. This is referred to as (N)o parity.

Because each bit in asynchronous communications is sent consecutively, it is easy to generalize asynchronous communications by stating that each character is wrapped (framed) by pre-defined bits to mark the beginning and end of the serial transmission of the

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Contents USB Single-Port Hub RS-422/485 Industry Canada Radio Frequency Interference StatementsUSB SINGLE-PORT HUB RS-422/485 NOM Statement Trademarks Used in this Manual Contents Specifications GeneralConnector Pin Assignments DB25 Male Name Pin # ModeIntroduction OverviewWhat the Package Includes Features Technical DescriptionInstallation Operating System InstallationSystem Installation Installation Hardware installation finished screen System Properties, Device Manager tab Configuration Electrical Interface SelectionSwitch Examples RS-530/422, 4-wire 485 master defaultAppendix A. Troubleshooting Before Calling Technical SupportCalling Black Box Shipping and Packaging Appendix B. Electrical Interfaces RS-530RS-422 RS-485 Appendix B Electrical Interfaces Appendix C. Asynchronous Communications Appendix C Asynchronous Communications USB SINGLE-PORT HUB RS-422/485 Copyright 2001. Black Box Corporation. All rights reserved