User manual SEAGATE DIAMONDMAX VL 30

[. . . ] DiamondMax VL 30 33073H4, 32305H3 31536H2, 30768H1 ® Part # 1480 All material contained herein Copyright © 2000 Maxtor Corporation. MaxFaxTM is a trademark of Maxtor Corporation. DiamondMax ®, Maxtor ® and No Quibble ® Service are registered trademarks of Maxtor Corporation. Other brands or products are trademarks or registered trademarks of their respective holders. [. . . ] When this command is received, the controller sets BSY and examines the Sector Count register contents. If they contain a valid and supported block count value, that value is loaded for all subsequent Read and Write Multiple commands, and execution of those commands is enabled. An invalid and unsupported block count in the register results in an Aborted Command error and disallows Read Multiple and Write Multiple commands. Write Commands Write Sector(s) Writes from 1 to 256 sectors, beginning at a sector specified in the Command Block. (A sector count of 0 requests 256 sectors. ) When the Command register is written, the drive sets the DRQ bit and waits for the host to fill the sector buffer with the data to be written. An interrupt is not generated to start the first buffer fill operation. Once the buffer is full, the drive resets DRQ, sets BSY, and begins command execution. If the drive is not already on the desired track, an implied seek is performed. The data loaded in the buffer is written to the data field of the sector, followed by the ECC bytes. Upon command completion, the Command Block registers contain the cylinder, head and sector number of the last sector written. The next time the buffer is ready to be filled during back-to-back Write Sector commands, DRQ is set and an interrupt is generated. After the host fills the buffer, DRQ is reset and BSY is set. If an error occurs, Write Sector operations terminate at the sector containing the error. The Command Block registers then contain the numbers of the cylinder, head and sector where the error occurred. The host may read the Command Block to determine the nature of that error, and on which sector it happened. A Write Long may be executed by setting the Long bit in the command code. The Write Long command writes the data and the ECC bytes directly from the sector buffer; the drive itself does not generate the ECC bytes. Restrict Write Long commands to PIO Mode 0. Write Verify Sector(s) Identical to the Write Sector(s) command, except that the requested sectors are verified immediately after being written. The verify operation reads (without transferring), and checks for data errors. Any errors encountered during this operation are reported. Write Sector Buffer Allows the host to overwrite the contents of the drive's sector buffer with a selected data pattern. When this command is received, the drive: 1. Sets BSY, Sets up the sector buffer for a write operation, Sets DRQ, Resets BSY and Generates an interrupt. The host may then write up to 256 words of data to the buffer. A disk write task begins to store the host data to disk. [. . . ] RAM is used for permanent information storage. Computer control programs are often stored in ROM applications. SERVOSYSTEM An automatic system for maintaining the read/write head on track; can be either "open loop, " "quasi-closed loop, " or "closed loop. " READ/WRITE HEAD The recording element which writes data to the magnetic media and reads recorded data from the media. SERVO TRACK A track on a servo surface. The prerecorded reference track on the dedicated servo surface of a disk drive. All data track positions are compared to their corresponding servo track to determine "off track"/"on track" position. RE-CALIBRATE The action of moving the head of a disk drive to cylinder zero. RECOVERABLEERROR A read error, transient or otherwise, falling within the capability of an ECC mechanism to correct, or able to overcome by rereading the data in question. SETTLING TIME The time it takes a head to stop vibrating, within specified limits, after it reaches the desired cylinder. SILICON Semiconductor material generally used to manufacture microprocessors and other integrated circuit chips. ROTATIONAL LATENCY The amount of delay in obtaining information from a disk drive attributable to the rotation of the disk. SMALL COMPUTER SYSTEM INTERFACE (SCSI) An intelligent interface that incorporates controller functions directly into the drive. RUN-LENGTH LIMITED An encoding process that repositions data bits and limits the length of zero bits in order to compress information being stored on disks. S. M. A. R. T. [. . . ]