Omega Vehicle Security OMG-COMM232-PCI manual Appendix C Electrical Interface, RS-232

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Appendix C – Electrical Interface

Appendix C - Electrical Interface

RS-232

Quite possibly the most widely used communication standard is RS-232. This implementation has been defined and revised several times and is often referred to as RS-232 or EIA/TIA-232. The IBM PC computer defined the RS-232 port on a 9 pin D sub connector and subsequently the EIA/TIA approved this implementation as the EIA/TIA-574 standard. This standard is defined as the 9-PositionNon-Synchronous Interface between Data Terminal Equipment and Data Circuit-Terminating Equipment Employing Serial Binary Data Interchange. Both implementations are in wide spread use and will be referred to as RS-232 in this document. RS-232 is capable of operating at data rates up to 20 Kbps at distances less than 50 ft. The absolute maximum data rate may vary due to line conditions and cable lengths. RS-232 is a single ended or unbalanced interface, meaning that a single electrical signal is compared to a common signal (ground) to determine binary logic states. The RS-232 and the EIA/TIA-574 specification define two types of interface circuits, Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE). The OMG- COMM+232.PCI is a DTE device.

Omega Engineering COMM+232.PCI

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Contents User’sGuide Mexico CanadaBenelux Czech RepublicContents Figures Introduction Factory Default SettingsOverview What’s IncludedClock Modes Card SetupAddress and IRQ selection For this Data Rate Choose this Data Rate Baud Rates and Divisors for the ‘DIV2’ modeOmega Engineering COMM+232.PCI Clocking Mode Divide By 1’ Baud Rates and Divisors for the ‘DIV1’ modeOmega Engineering COMM+232.PCI Operating System Installation Windows 95/98/NT InstallationHardware Installation WindowsInterrupts Technical DescriptionConnector Pin Assignments RS-232 Why use an ISP?Specifications Appendix a Troubleshooting Appendix B How To Get Assistance Appendix C Electrical Interface Appendix D Asynchronous Communications Asynchronous Communications Bit DiagramAppendix E Silk-Screen Appendix F Compliance Notices WARRANTY/DISCLAIMER Temperature