WO R K I N G W I T H T H E C P U

MemoryManagement Unit (MMU)

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Table index

Section index

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Translation table base

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Translation base

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Table index

 

 

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Section first-level descriptor

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Section base address

 

SBZ

 

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Physical address

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Section base address

Section index

Second-level descriptor

Second-level descriptor format

The base address of the page table to be used is determined by the descriptor returned (if any) from a first-level fetch — either a coarse page table descriptor or a fine page table descriptor. The page table is then accessed and a second-level descriptor returned.

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Large page

Large page base address

 

 

 

AP3

AP2

AP1

AP0

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Small page

Small page base address

 

 

 

AP3

AP2

AP1

AP0

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Tiny page

Tiny page base address

 

 

 

 

 

 

 

 

 

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Second-level descriptor pages

A second-level descriptor defines a tiny, small, or large page descriptor, or is invalid:

A large page descriptor provides the base address of a 64 KB block of memory. A small page descriptor provides the base address of a 4 KB block of memory.

114Hardware Reference NS9215

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Digi NS9215 manual Second-level descriptor Second-level descriptor format, Second-level descriptor pages

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.