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

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MMU faults and CPU aborts. .

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M M U f a u l t s a n d C P U a b o r t s

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The MMU generates an abort on these types of faults: Alignment faults (data accesses only) Translation faults

Domain faults Permission faults

In addition, an external abort can be raised by the external system. This can happen only for access types that have the core synchronized to the external system:

Alignment fault checking

Fault Address and Fault Status registers

Page walks

Noncached reads

Nonbuffered writes

Noncached read-lock-write sequence (SWP)

Alignment fault checking is enabled by the A bit in the R1: Control register. Alignment fault checking is not affected by whether the MMU is enabled. Translation, domain, and permission faults are generated only when the MMU is enabled.

The access control mechanisms of the MMU detect the conditions that produce these faults. If a fault is detected as a result of a memory access, the MMU aborts the access and signals the fault condition to the CPU core. The MMU retains status and address information about faults generated by the data accesses in the Data Fault Status register and Fault Address register (see “Fault Address and Fault Status registers” on page 119).

The MMU also retains status about faults generated by instruction fetches in the Instruction Fault Status register.

An access violation for a given memory access inhibits any corresponding external access to the AHB interface, with an abort returned to the CPU core.

On a data abort, the MMU places an encoded four-bit value — the fault status — along with the four-bit encoded domain number in the Data Fault Status register. Similarly, on a prefetch abort, the MMU places an encoded four-bit value along with the four-bit encoded domain number in the Instruction Fault Status register. In addition, the MVA associated with the data abort is latched into the Fault Address

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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.
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