I2O Support

•All MFA counters maintained by the 21555 may be individually loaded with any data value by writing a 1 to bit 31 of the corresponding counter Dword offset. When either the Inbound Free_List Counter or the Outbound Post_List Counter is loaded, the 21555 discards any prefetched data in the corresponding prefetch buffer.

•The 21555 actions are unpredictable in response to primary bus transactions addressing the I2O Outbound or Inbound Queues while a corresponding counter load is occurring on the secondary bus. The counters will load and increment even if the I2O Enable is not set.

•The 21555 I2O counters are consistent with the number of entries in the various lists from the secondary bus, or local memory, point of view. This means that counters do not include any MFAs that exist in the 21555 posting or prefetch buffers. The counters include only those entries that are present in local memory. The Outbound Free_List and Inbound Post_List pointers are consistent with the primary bus viewpoint. This means that the value of the head and tail pointers that the 21555 implements includes any data in the 21555 posted write buffers as part of the lists. The pointers corresponding to the Outbound Post_List and Inbound Free_List should not be considered to be consistent with the number of entries in these lists.

•The 21555 I2O counters are consistent with the number of entries in the various lists from the secondary bus, or local memory, point of view. This means that counters do not include any MFAs that exist in the 21555 posting or prefetch buffers. The counters include only those entries that are present in local memory.

•When the I2O Enable bit is disabled after the I2O message unit is operational, additional reads to 40h and 44h returns data that remains in the corresponding prefetch buffer until the prefetch buffer is emptied. After the prefetch buffer is emptied, the 21555 returns FFFF FFFFh.

•When the secondary interface Master Enable bit is disabled:

—Reads to 40h and 44h are FFFF FFFFh.

—Writes to 40h and 44h are queued in the downstream posted write queue, but not delivered until the master enable bit is set.

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21555 specifications

The Intel 21555 is a prominent microprocessor developed by Intel, designed to cater to a variety of computing needs. This processor marks a significant step forward in Intel's lineup and underscores the company's commitment to advancing technology in personal computing, enterprise solutions, and beyond.

One of the standout features of the Intel 21555 is its advanced architecture. It utilizes a multi-core design, enabling improved performance through parallel processing. This architecture allows multiple applications to run seamlessly without a decline in speed. The cores are built on a cutting-edge manufacturing process that enhances energy efficiency while maintaining high clock speeds.

The Intel 21555 supports a wide range of technologies, including Intel Turbo Boost, which enables dynamic adjustments to the processor’s performance based on workload demands. This feature allows the processor to accelerate its speed during intensive tasks, providing users with a responsive experience when it matters the most.

Another key characteristic of the Intel 21555 is its support for integrated graphics. With Intel UHD Graphics technology, users can enjoy enhanced visuals for everyday tasks such as video playback, web browsing, and light gaming. This eliminates the need for a separate graphics card for many users, particularly in home office or light gaming scenarios.

Security is a significant focus in the design of the Intel 21555. It includes built-in hardware-based security features like Intel Trusted Execution Technology and Secure Boot. These features help protect against various types of threats, ensuring that user data remains secure from malicious attacks.

The Intel 21555 is also optimized for use with Intel's platform technologies, including Intel Optane memory and Intel Rapid Storage Technology. These technologies work together to deliver faster boot times and improved system responsiveness, making computing more efficient for users.

Furthermore, the Intel 21555 is designed to support virtualization technologies, allowing multiple operating systems to run concurrently without compromising performance. This is particularly useful for developers and businesses that rely on virtualization for testing and development environments.

In summary, the Intel 21555 is a powerful and versatile processor that reflects Intel's ongoing innovation in the computing space. With its multi-core architecture, enhanced graphics capabilities, strong security features, and advanced technologies, it stands out as an excellent choice for a wide range of applications, serving both casual users and professionals alike.
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