User manual MAXTOR CP30204

[. . . ] Cougar Series CP30204 Intelligent Disk Drive Product Manual 00501-043 Revision B April, 1992 3081 Zanker Road San Jose, CA 95134-2128 (408) 456-4500 Notice Conner Peripherals makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Conner Peripherals shall not be liable for errors contained herein or for incidental consequential damages in connection with the furnishing, performance or use of this material. reserves the right to change, without notification, the specifications contained in this manual. © Copyright Conner Peripherals, Inc. [. . . ] During a read long, the drive does not check the ECC bytes to determine there has been any type of data Error. Data bytes are 16 bit transfers and ECC bytes are 8 bit transfers. 12. 3 Write Sector(s) - 3X This command will write from 1 to 256 sectors as specified in the Task File (sector count equal to 0 requests 256 sectors), beginning at the specified sector. As soon as the Command Register is written, the drive waits for the Host to fill the sector buffer with the data to be written. No interrupt is generated to start the first buffer fill operation. Once the buffer is full, the drive sets BSY and begins command execution. Revision B - 47 - The Error bit (ERR) is set in the Status Register and the Error Register is updated, (1) if bits 2 & 3 are not equal to zero, (then the Aborted Command bit, ABRT, is set), or (2) if incorrect Task File parameters are passed, the ID Not Found Error, IDNF, is set. If the drive is not already on the desired track, an implied SEEK is performed. Once at the desired track, the drive begins searching for the appropriate ID field. If the ID is correct, the data loaded in the buffer is written to the data field of the sector, followed by the ECC bytes. Upon command completion, the Task File Registers contain the cylinder, head, and sector number of the last sector written. The sector count is zero after successful execution of the command. Multiple sector writes set DRQ and generate an interrupt each time the buffer is ready to be filled. DRQ is reset and BSY is set immediately when the Host fills the sector buffer. If an Error occurs during a multiple sector write, it will terminate at the sector where the error occurs. The Task File indicates the location of the sector where the error occurred. The Host may then read the Task File to determine what error has occurred, and on which sector. If no error is detected, the cylinder, head, and sector Registers are updated to point at the next sequential sector. 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 will not generate the ECC bytes itself for the write long command. Data byte transfers are 16 bits, ECC bytes are 8 bit transfers. - 48 - Revision B 12. 4 Verify Sectors - 4X This command functions similarly to the READ SECTORS command except that no data is transferred to the host and at completion of the command the CORR bit is set if software ECC correction was required. The drive remains BUSY until all data is verified. If LOOK AHEAD's are active, the VERIFY command will also work the same as when a READ is performed. [. . . ] This means that the only way a drive can respond properly to a command is for the drive microprocessor to be active. When BUSY is active, the drive has read and write access to the Task File Registers and the Host can only read the Status Register and Alternate Status Register of the Task File. Any attempted Host read of a Task File Register while BSY is active, results in reading the Status Register. When BUSY is inactive, the Host has read and write access to all Task File Registers. - 74 - Revision B 14. 4 Conner Master/Slave The drive is equipped with a -C/D jumper. [. . . ]