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Digi NS9215 manual Dpll operation Adjustment ranges and output clocks

Models: NS9215

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DPLL-tracked bit cell boundaries

NRZ and NRZI data encoding

Biphase data encoding

S E R I A L C O N T RO L M O D U L E : H D L C

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DPLL operation: Adjustment ranges and output clocks..

 

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The DPLL counter normally counts by 16 but if a transition occurs earlier or later than expected, the count is modified during the next count cycle.

If the transition occurs earlier than expected, the bit cell boundaries are early with respect to the DPLL-tracked cell boundaries and the count is shortened by either one or two counts.

If the transition occurs later than expected, the bit cell boundaries are late with respect to the DPLL-tracked bit cell boundaries and the count is lengthened by either one or two counts.

How far off the DPLL-tracked bit cell boundaries are determines whether the count is adjusted by one or two. This tracking allows for minor differences in the transmit and receive clock frequencies.

With NRZ and NRZI data encoding, the DPLL counter runs continuously and adjusts after every receive data transition.

Because NRZ encoding does not guarantee a minimum density of transitions, the difference between the sending data rate and the DPLL output clock rate must be very small, and depends on the longest possible run of zeros in the received frame.

NRZI encoding guarantees at least one transition every six bits (with the inserted zeroes). Because the DPLL can adjust by two counts every bit cell, the maximum difference between the sending data rate and the DPLL output clock rate is 1/48 (~2%).

With biphase data encoding, the DPLL works in multiple-access conditions where there may not be flags on the idle line. The DPLL properly generates an output clock based on the first transition in the leading zero of an opening flag. Similarly, the DPLL requires only the completion of the closing flag to provide the extra two clocks to the receiver to properly assemble the data.

In biphase-level mode, this means the transition that defines the last zero of the closing flag.

In the biphase-mark and biphase-space modes, this means the transition that defines the end of the last zero of the closing flag.

D P L L o p e r a t i o n : A d j u s t m e n t r a n g e s a n d o u t p u t c l o c k s

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This figure shows the adjustment ranges and output clock for the different DPLL modes of operation:

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Digi NS9215 manual Dpll operation Adjustment ranges and output clocks
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NS9215 specifications

The Digi NS9215 is a powerful solution designed for industrial applications that require reliable connectivity and robust performance. Built on a foundation of advanced technologies, the NS9215 serves as a versatile networking device that meets the demands of automation, remote monitoring, and data acquisition.

One of the standout features of the Digi NS9215 is its multi-protocol support. It is capable of handling various communication protocols, including Ethernet, Serial, and Wireless, making it ideal for integration into heterogeneous environments. This flexibility enables users to connect legacy devices to modern networks seamlessly, facilitating smoother data communication across different platforms.

The NS9215 is equipped with powerful processing capabilities, featuring an integrated processor that ensures efficient data handling. This enables the device to perform complex data tasks without compromising performance. Its high-speed connectivity options also allow for rapid data transmission, which is crucial for real-time applications in industrial settings.

Another critical characteristic of the Digi NS9215 is its reliability in harsh environments. Built to withstand extreme temperatures, humidity, and electrical interference, this device assures consistent operation even in challenging conditions. Its rugged design minimizes the risk of failure, making it suitable for deployment in various industrial environments.

Security is a top priority for the Digi NS9215. It comes with advanced security features that protect sensitive data during transmission and prevent unauthorized access. Employing encryption protocols and secure authentication methods, the NS9215 ensures that data integrity and confidentiality are maintained throughout its operation.

The user-friendly interface of the NS9215 allows for easy configuration and management. This ease of use reduces the time required for installation and setup, enabling quick deployment in field operations. Additionally, remote management capabilities enhance operational efficiency, allowing users to monitor device performance and make adjustments from anywhere.

Furthermore, the NS9215 supports extensive scalability options. As organizations grow and evolve, the ability to scale up or adapt the networking capabilities becomes essential. With its modular design, the NS9215 can easily accommodate additional devices and protocols, ensuring longevity and continued relevance in a rapidly changing technological landscape.

In conclusion, the Digi NS9215 is a robust networking device designed for a wide range of industrial applications. Its multi-protocol support, reliability, security features, user-friendly interface, and scalability make it a valuable addition to any industrial network infrastructure, delivering performance and efficiency that businesses can depend on for critical operations.