INTERFACECOMMANDS

Read Commands

Read Sector(s)

Reads from 1 to 256 sectors, as specified in the Command Block, beginning at the specified sector. (A sector count of 0 requests 256 sectors.) Immediately after the Command register is written, the drive sets the BSY bit and begins execution of the command. If the drive is not already on the desired track, an implied seek is performed.

Once at the desired track, the drive searches for the data address mark of the requested sector. The data address mark must be recognized within a specified number of bytes, or the Data Address Mark Not Found error will be reported. Assuming the data address mark is found:

1.The data field is read into the sector buffer.

2.Error bits are set (if an error was encountered).

3.The DRQ bit is set.

4.An interrupt is generated.

The DRQ bit is always set, regardless of the presence or absence of an error condition after the sector. Upon command completion, the Command Block registers contain the numbers of the cylinder, head and sector of the last sector read. Back-to-back sector read commands set DRQ and generate an interrupt when the sector buffer is filled at the completion of each sector. The drive is then ready for the data to be read by the host. DRQ is reset and BSY is set immediately when the host empties the sector buffer.

If an error occurs during Read Sector commands, the read terminates at the sector where the error occurred. The host may then read the Command Block to determine the nature of that error, and the sector where it happened. If the error type is a correctable or an non-correctable data error, the flawed data is loaded into the sector buffer.

A Read Long command sets the Long bit in the command code and returns the data and the ECC bytes in the data field of the specified sector. During a Read Long, the drive does not check the ECC bytes to determine if there has been a data error. The Read Long command is limited to single sector requests.

Read Verify Sector(s)

Identical to the Read Sector(s) command, except that:

1.DRQ is never set,

2.No data is transferred back to the host and

3.The long bit is not valid.

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Maxtor 88400D8, 86480D6, 84320D4, 83240D3, 82160D2 specifications Read Commands, Read Sectors, Read Verify Sectors
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82160D2, 84320D4, 2160, 83240D3, 86480D6 specifications

Maxtor, known for its innovative storage solutions, produced several pivotal hard drive models during the late 1990s and early 2000s, namely the Maxtor 88400D8, 86480D6, 83240D3, 2160, and 84320D4. Each of these drives showcased unique features and technologies that catered to various computing needs.

The Maxtor 88400D8 stood out with its impressive storage capacity of 8.4 GB, which was considerable at the time. It employed the IDE interface, ensuring broad compatibility with most personal computers. The drive utilized a 5400 RPM spindle speed, optimizing data transfer rates for everyday applications. With a 2 MB cache, it facilitated smoother data retrieval, making it a reliable choice for both home and office use. This model exemplified Maxtor's commitment to enhancing user experience through advanced technologies.

Another noteworthy model, the Maxtor 86480D6, offered an 8.6 GB storage capacity, predicated on similar design principles as the 88400D8. It also featured a 5400 RPM spindle speed and an IDE interface. Its greater data density further improved performance, reducing the time required for searching and accessing large volumes of information. The 86480D6 was particularly favored by users with intensive storage needs, such as graphic designers and multimedia creators.

The Maxtor 83240D3, with a storage capacity of 3.2 GB, catered to users seeking a balance between performance and size. This drive also operated at 5400 RPM and featured an IDE interface. Its compact size made it an attractive option for entry-level systems and budget-conscious consumers who needed dependable storage without excessive capacity.

The Maxtor 2160 and 84320D4 models further diversified the line with distinct features suitable for different user segments. The 2160 offered 2.1 GB of storage, appealing particularly to users of basic office applications. In contrast, the 84320D4 provided 4.3 GB of space, marking a mid-range option for users requiring additional capacity without leapfrogging into high-end solutions.

All these Maxtor models incorporated technologies enhancing reliability and performance, such as Advanced Format technology, which optimized data organization, ensuring efficient use of storage space. These drives also showcased an emphasis on low power consumption, which aligned with growing concerns over energy efficiency in computing.

In summary, the Maxtor 88400D8, 86480D6, 83240D3, 2160, and 84320D4 were crucial entries in the hard drive market, bringing forth features that addressed the diverse needs of users, from casual consumers to professionals demanding superior performance. Their legacy continues to influence hard drive design and performance standards in contemporary storage solutions.
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