Set Features command, 0CH | Seagate ST3750840ACE guide

4.1.3Set Features command

This command controls the implementation of various features that the drive supports. When the drive receives this command, it sets BSY, checks the contents of the Features register, clears BSY and generates an inter- rupt. If the value in the register does not represent a feature that the drive supports, the command is aborted. Power-on default has the read look-ahead and write caching features enabled. The acceptable values for the Features register are defined as follows:

02H	Enable write cache (default).
03H	Set transfer mode (based on value in Sector Count register).
	Sector Count register values:

	00H	Set PIO mode to default (PIO mode 2).
	01H	Set PIO mode to default and disable IORDY (PIO mode 2).
	08H	PIO mode 0
	09H	PIO mode 1
	0AH	PIO mode 2
	0BH	PIO mode 3
	0CH	PIO mode 4 (default)
	20H	Multiword DMA mode 0
	21H	Multiword DMA mode 1
	22H	Multiword DMA mode 2
	40H	Ultra DMA mode 0
	41H	Ultra DMA mode 1
	42H	Ultra DMA mode 2
	43H	Ultra DMA mode 3
	44H	Ultra DMA mode 4
	45H	Ultra DMA mode 5
55H	Disable read look-ahead (read cache) feature.
82H	Disable write cache.
AAH	Enable read look-ahead (read cache) feature (default).
F1H	Report full capacity available

Note. At power-on, or after a hardware or software reset, the default values of the features are as indi- cated above.

DB35.3 Series PATA Product Manual, Rev. B

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Seagate ST3750840ACE manual Set Features command, 0CH

Contents

DB35.3 Series Pata Page Contents DB35.3 Series Pata Product Manual, Rev. B List of Figures DB35.3 Series Pata Product Manual, Rev. B Introduction DB35.3 Series Pata Product Manual, Rev. B Specification summary table Drive specifications Drive specification ST3750840ACE ST3500830ACE ST3400820ACE DB35.3 Series Pata Product Manual, Rev. B Drive specification ST3320820ACE ST3300820ACE ST3250820ACE DB35.3 Series Pata Product Manual, Rev. B Cylinders Read/write heads Sectors per track 16,383 Default logical geometryLBA mode Formatted capacity 750GB 500GB 400GB 320GB 300GB 250GB Physical characteristicsDrive specification Recording and interface technology Power specifications Seek timeStart/stop times DC power requirements Standby mode Conducted noise Typical current profile Sleep mode Power-management modesActive mode Idle mode Environmental specifications 4 Disc models ShockOperating shock Nonoperating shock Disc models Acoustics Fluid Dynamic Bearing FDB motor acousticsIdle CE seek profile Agency certification Safety certificationElectromagnetic immunity Reliability FCC verification Electromagnetic compatibilityKorean RRL Australian C-Tick N176 Environmental protection Corrosive environmentEuropean Union Restriction of Hazardous Substances RoHS DB35.3 Series Pata Product Manual, Rev. B Handling and static discharge precautions Configuring and mounting the drive Breather filter hole location Breather filter hole precautions Cable-select option Jumper settingsMaster/slave configuration Drive as master with a non-ATA-compatible slave Ultra ATA/100 cable Drive mounting Mounting dimensions-top, side and end view DB35.3 Series Pata Product Manual, Rev. B ATA interface signals and connector pins Pins and supported ATA signalsATA interface Command name Command code in hex Supported ATA commands F4H Word Description Value Identify Device command Xx07H Bit Word Description if bit is set to Bit Word 0CH Set Features command Code in features Register A.R.T. command 4 S.M.A.R.T. commands Technical Support Seagate Technology support servicesInternet Presales Support Warranty Service Data Recovery Services Authorized Service CentersData Recovery Services Call Center Toll-free Direct dial Index Page TMR DB35.3 Series Pata Product Manual, Rev. B Page Seagate Technology LLC