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

MemoryManagement Unit (MMU)

Section descriptor

bit description

Bits

Description

 

 

 

 

[31:20]

Forms the corresponding bits of the physical address for a section.

 

 

 

 

[19:12]

Always written as 0.

 

 

 

 

[11:10]

Specify the access permissions for this section.

 

 

 

 

[09]

Always written as 0.

 

 

 

 

[8:5]

Specifies one of the 16 possible domains (held in the Domain and Access Control

 

 

register) that contain the primary access controls.

 

 

 

 

4

Should be written as 1, for backwards compatibility.

 

 

 

 

[3:2]

Indicate if the area of memory mapped by this section is treated as writeback cachable,

 

 

write-through cachable, noncached buffered, or noncached nonbuffered.

 

 

 

 

[1:0]

Must be 10 to indicate a section descriptor.

 

 

 

Coarse page table descriptor

Coarse page table descriptor format

Coarse page table descriptor bit description

A coarse page table descriptor provides the base address of a page table that contains second-level descriptors for either large page or small page accesses. Coarse page tables have 256 entries, splitting the 1 MB that the table describes into 4 KB blocks.

Note: If a coarse page table descriptor is returned from the first-level fetch, a second-level fetch is initiated.

31

10

9

8

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

Coarse page table base address

 

S

Domain

 

1

SBZ

0

1

 

B

 

 

 

Z

 

 

 

 

 

 

 

Bits

Description

 

 

[31:10]

Forms the base for referencing the second-level descriptor (the coarse page table index

 

for the entry derived from the MVA).

 

 

9

Always written as 0.

 

 

[8:5]

Specifies one of the 16 possible domains (held in the Domain Access Control registers)

 

that contain the primary access controls.

 

 

4

Always written as 1.

 

 

[3:2]

Always written as 0.

 

 

[1:0]

Must be 01 to indicate a coarse page descriptor.

 

 

Fine page table

A fine page table descriptor provides the base address of a page table that contains

descriptor

second-level descriptors for large page, small page, or tiny page accesses. Fine

112Hardware Reference NS9215

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Digi NS9215 manual Section descriptor Bit description, Fine page table, Descriptor, Bits Description

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.