Omega Engineering RS-422/485 manual Clock Modes, DIV4 DIV2

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Card Setup

Clock Modes

The OMG-ULTRA-COMM422employs a unique clocking option that allows the end user to select from divide by 4, divide by 2 and divide by 1 clocking modes. These modes are selected at Headers J1C through J4C.

To select the Baud rates commonly associated with COM: ports (i.e. 2400, 4800, 9600, 19.2, … 115.2K Bps ) place the jumper in the divide by 4 mode (silk-screen DIV4).

DIV4

DIV2

DIV1

Figure 12 - Clocking Mode 'Divide By 4’

To double these rates up to a maximum rate for 230.4K bps place the jumper in the divide by 2 (silk-screen DIV2) position.

DIV4

DIV2

DIV1

Figure 13 - Clocking Mode 'Divide By 2’

To select the maximum data rate (460.8K bps) place the jumper in the divide by 1 (silk-screen DIV1) position.

DIV4

DIV2

DIV1

Figure 14 - Clocking Mode 'Divide By 1’

OMG-ULTRA-COMM422

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Contents User’sGuide Benelux CanadaMexico Czech RepublicContents Figures Overview Factory Default SettingsIntroduction What’s IncludedAddress Selection Card SetupSwitch Port Switch Settings Address lines à Address Selected Port # Connector Location Address Example Base=2E0Jumper Selections IRQ SelectionJ1A Interrupt ModesRS-485 Enable Modes Interface Mode Examples J1D J4D Headers J1D- J4D, RS-422Headers J1D- J4D, RS-485 ‘RTS’ Enabled, with ‘No Echo’ Line Termination Name FunctionClock Modes DIV4 DIV2For this Data Rate Choose this Divisor Baud Rates and Divisors for the ‘Div1’ modeFor this Data Rate Choose this Data Rate Baud Rates and Divisors for the ‘Div2’ mode Other Operating Systems InstallationOperating System Installation For Windows Users Technical Description FeaturesModem Control Signal Considerations Interrupts Why use an ISP? Signal Name Pin # Mode Connector Pin Assignments DB-9 Pin AssignmentsDB-37 Connector Pin Assignments Port #Specifications Appendix a Troubleshooting OMG-ULTRA-COMM422 Appendix B How To Get Assistance RS-485 Appendix C Electrical InterfaceRS-422 Asynchronous Communications Bit Diagram Appendix D Asynchronous CommunicationsAppendix E Silk-Screen Appendix F Compliance Notices WARRANTY/DISCLAIMER Temperature

RS-422/485 specifications

Omega Engineering is a renowned leader in the field of measurement and control technologies, particularly in the realm of data communication for industrial automation. The RS-422 and RS-485 protocols are part of Omega's robust offering, designed to facilitate reliable and efficient data transmission over relatively long distances. These protocols are widely used in various applications ranging from industrial machinery to building automation systems.

One of the main features of RS-422 is its ability to support long-distance communication, allowing data to be transmitted up to 4,000 feet (approximately 1,200 meters) at speeds of up to 10 Mbps. This is achieved through the use of differential signaling, which provides improved noise immunity compared to single-ended signaling systems. RS-422 employs a single transmitter and multiple receivers, making it ideal for point-to-multipoint configurations.

On the other hand, RS-485 extends the capabilities of RS-422 by allowing multiple devices to be connected on the same bus. It supports up to 32 devices, which can be either transmitters or receivers, making it exceptionally versatile for networking applications. RS-485 can communicate effectively over distances up to 4,000 feet and at speeds of 10 Mbps as well. This makes it an attractive option for applications where several devices need to communicate with a central controller.

An essential characteristic of both protocols is their resilience to electromagnetic interference, which is often a concern in industrial environments. The differential signaling used in RS-422 and RS-485 reduces noise susceptibility, ensuring data integrity even in challenging conditions. Additionally, these protocols function effectively in half-duplex or full-duplex modes, providing flexibility based on application requirements.

Moreover, Omega Engineering’s implementations of RS-422 and RS-485 comply with established standards, ensuring compatibility with a wide range of devices. This interoperability is crucial for seamless integration into existing systems and enhancing overall productivity.

In summary, Omega Engineering's RS-422 and RS-485 technologies offer robust, reliable, and versatile solutions for data communication in industrial settings. With features such as long-distance communication, multiple device connections, and exceptional noise immunity, these protocols continue to serve as foundational technologies in various automation and control applications. As industries evolve, Omega Engineering remains committed to advancing these technologies to meet the growing demands of modern data communication.