Set Features command, 0CH | Seagate ST38421A, ST32112A, ST36421A

U4 Family Product Manual, Rev. D

29

11Ultra DMA mode 3 is currently active.

12Ultra DMA mode 4 is currently active.

Bit Word 93

131=80-conductor cable detected, CBLID above VIH 0=40-conductor cable detected, CBLID below VIL

3.2.3Set 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 interrupt. 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

Image 37

Seagate ST38421A, ST32112A, ST36421A, ST34311A manual Set Features command, 0CH

Contents

Product Manual Page Product Manual Page Contents ATA interface Configuring and mounting the drive Seagate Connfidential Review Draft not for Distribution Figures Seagate Confidential Review Draft not for Distribution Introduction Specification summary table Track-to-track seek time Msec typical Vibration, nonoperating LBA Mode Default logical geometryFormatted capacity Physical organization Drive Specification ST38421A, ST36421A ST34311A, ST32112A Physical characteristicsRecording and interface technology Seek time Power consumption Power specificationsSpinup power Start/stop times Read/Write power and current Seek ModeOperating power and current Idle mode power Typical current profile Power Mode Typical Watts Typical Amps RMS 12VCurrent amps Time seconds Conducted noise Power-management modesVoltage tolerance Temperature gradient Environmental tolerances Ambient temperatureHumidity Relative Humidity Altitude Wet bulb temperatureShock Operating shock Nonoperating vibration Operating vibrationDrive acoustics Electromagnetic susceptibility Agency certification Safety certificationReliability Electromagnetic compatibility Australian C-Tick FCC verification U4 Family Product Manual, Rev. D Handling and static-discharge precautions Configuring and mounting the drive Master/slave jumper settings Jumper settings Master/slave configuration Cable-select option Important mounting precautionsUltra ATA/66 cable Drive mounting Mounting dimensions-top, side and end view ATA interface ATA interface signals and connector pins O pins and supported ATA signals Command name Command code in hex ATA-standard commands ATA Interface commands Supported ATA commands Command name Identify Drive commandATA-standard power-management commands ATA-standard security commands Word Description 27-46 Drive model number 40 Ascii char Multiword DMA active and modes 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. commandsPage U4 Family Product Manual, Rev. D U4 Family Product Manual, Rev. D