INTERFACE COMMANDS

Read DMA

Multi-word DMA

Identical to the Read 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 and status is available.

Ultra DMA

With the Ultra DMA Read protocol, the control signal (DSTROBE) 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 DSTROBE to the drive during an Ultra DMA data in burst.

During an Ultra DMA Read burst, the drive 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 DSTROBE edge to latch the data. Both edges of DSTROBE are used for data transfers.

Any unrecoverable error encountered during execution of a Read DMA command terminates data transfer after the transfer of all sectors prior to the sector where the error was detected. The sector in error is not transferred. The drive generates an interrupt to indicate that data transfer has terminated and status is available. The error posting is identical to the Read Sector(s) command.

Read Multiple

Performs similarly to the Read Sector(s) command, except that for each READ MULTIPLE command data transfers are multiple sector blocks and the Long bit is not valid.

Execution is also similar to that of the READ SECTOR(S) command, except that:

1.Several sectors are transferred to the host as a block, without intervening interrupts.

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

The block count consists of the number of sectors to be transferred as a block. (The block count is programmed by the Set Multiple Mode command, which must be executed prior to the Read Multiple command.) READ LONG command is limited to single sector requests.

When the Read 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 Read 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 Read Multiple commands are disabled.

The controller reports disk errors encountered during Read Multiple commands at the start of the block or partial block transfer. However, DRQ still sets, and the transfer occurs normally, along with the transfer of any corrupt data. Remaining block data from the following the sector in error is not valid.

If the Sector Count register contains 0 when the Set Multiple Mode command is issued, Read Multiple and Write Multiple commands are disabled; no error is returned. Once the appropriate action has been taken, the controller resets BSY and generates an interrupt. At power up, or after a hardware or software reset, Read Multiple and Write Multiple commands are disabled by default.

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Maxtor 98196H8, 96147H6 specifications Read DMA

96147H6, 98196H8 specifications

The Maxtor 98196H8 and 96147H6 are notable hard drive models that were part of Maxtor's diverse range of storage solutions. Both models were designed to cater to various computing needs and display characteristics that made them reliable, high-performance options during their time in the market.

The Maxtor 98196H8 is a 19.1 GB hard drive that utilizes the IDE interface, which is known for its ease of use and compatibility with a broad range of motherboards. This model features a rotational speed of 5400 RPM, striking a balance between performance and power consumption. With a data transfer rate of up to 33 MB/s, the 98196H8 is capable of efficiently handling average workloads, making it suitable for everyday computing tasks such as word processing, web browsing, and media playback.

One standout characteristic of the 98196H8 is its shock protection technology, which enhances durability and reduces the risk of data loss from accidental drops. The drive uses fluid dynamic bearing (FDB) motors for quieter operation and increased reliability. Additionally, Maxtor's proprietary technology, including the SoftSonic feature, allows for reduced operational noise levels, making it an appealing choice for users who prioritize a quiet working environment.

On the other hand, the Maxtor 96147H6 boasts a slightly larger capacity of 14.7 GB and shares similar interface traits and rotational speed as the 98196H8. With a focus on providing reliable storage for desktop applications, this model leverages Maxtor's advanced data recovery solutions, which help ensure that users can restore lost data in the event of drive failures. Its high-capacity storage makes it well-suited for users dealing with larger files or needing additional space for various applications and media.

Both models are equipped with Maxtor's Error Recovery Control technology, which actively manages potential read/write errors, ensuring data integrity during storage and retrieval processes. This is especially beneficial for users handling critical information or relying on the storage for important projects.

In conclusion, the Maxtor 98196H8 and 96147H6 hard drives exemplified Maxtor's dedication to creating dependable storage solutions for consumers. With their variety of capacities, advanced technologies, and characteristics tailored to improve reliability and performance, they served many users well during their availability in the market.