INTERFACECOMMANDS

Write Multiple

Performs similarly to the Write Sector(s) command, except that:

1.The controller sets BSY immediately upon receipt of the command,

2.Data transfers are multiple sector blocks and

3.The Long bit and Retry bit is not valid.

Command execution differs from Write Sector(s) because:

1.Several sectors transfer to the host as a block without intervening interrupts.

2.DRQ qualification of the transfer is required at the start of the block, not on each sector.

The block count consists of the number of sectors to be transferred as a block and is programmed by the Set Multiple Mode command, which must be executed prior to the Write Multiple command. When the Write Multiple command is issued, the Sector Count register contains the number of sectors requested — not the number of blocks or the block count.

If the number of sectors is not evenly divisible by the block count, as many full blocks as possible are transferred, followed by a final, partial block transfer. This final, partial block transfer is for N sectors, where N = (sector count) modulo (block count)

The Write Multiple operation will be rejected with an Aborted Command error if attempted:

1.Before the Set Multiple Mode command has been executed, or

2.When Write Multiple commands are disabled.

All disk errors encountered during Write Multiple commands report after the attempted disk write of the block or partial block in which the error occurred.

The write operation ends with the sector in error, even if it was in the middle of a block. When an error occurs, subsequent blocks are not transferred. When DRQ is set at the beginning of each full and partial block, interrupts are generated.

Write DMA

Multi-word DMA

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

1.The host initializes a slave-DMA channel prior to issuing the command,

2.Data transfers are qualified by DMARQ and are performed by the slave-DMA channel and

3.The drive issues only one interrupt per command to indicate that data transfer has terminated at status is available.

Ultra DMA

With the Ultra DMA Write protocol, the control signal (HSTROBE) that latches data from DD(15:0) is generated by the devices which drives the data onto the bus. Ownership of DD(15:0) and this data strobe signal are given to the host for an Ultra DMA data out burst.

During an Ultra DMA Write burst, the host always moves data onto the bus, and, after a sufficient time to allow for propagation delay, cable settling, and setup time, the sender shall generate a HSTROBE edge to latch the data. Both edges of HSTROBE are used for data transfers.

Any error encountered during Write DMA execution results in the termination of data transfer. The drive issues an interrupt to indicate that data transfer has terminated and status is available in the error register. The error posting is the same as that of the Write Sector(s) command.

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Maxtor 82160D2, 86480D6, 88400D8, 84320D4, 83240D3 specifications Write Multiple, Write DMA

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.