U10 Family Product Manual, Rev. A

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9Ultra DMA mode 1 is currently active.

10Ultra DMA mode 2 is currently active.

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

3.1.3Set 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 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