Intel 460GX 10.5.6IFB Timing Settings, 10.5.6.1DMA/PIO Timing Settings, Table 10-7.IFB Drive Mode Based on DMA/PIO Capabilities

IFB Usage Considerations

10.5.6IFB Timing Settings10.5.6.1DMA/PIO Timing Settings

In Table 10-7, ‘x’=depends on the type of drive installed, ‘1’=enabled, and ‘0’=disabled.

Ultra DMA mode settings are completely independent of the following timings.

Table 10-7. IFB Drive Mode Based on DMA/PIO Capabilities

			Fast PIO	Non Ultra DMA	DMA		IORDY
Drive’s Best	Drive’s Best	IFB	Supported?	Non Ultra DMA	DMA	Prefetch and		Fast Timing
			Supported?	Supported?	Timing
			Best PIO	Supported?	Timing		Sample
DMA	PIO	Timing	Best PIO	Best DMA	Enable	Posting	Sample	Bank Drive
DMA	PIO	Timing	Mode >=	Best DMA	Enable	Posting	Point Enable	Bank Drive
Capability	Capability	Mode	Mode >=	Mode is {SW2,	Only Select	Enable Select	Point Enable	Select
Capability	Capability	Mode	Best DMA	Mode is {SW2,	Only Select	Enable Select	Select	Select
			Best DMA	MW1, MW2}	a		Select
			Mode	MW1, MW2}
			Mode

N/A	PIO0/1/	Mode 0	No	No	Disabled	Enabled	Disabled	Disabled
(DMA not	Compatible					(if fixed disk)
supported)

N/A	PIO2	Mode 2	Yes	No	Disabled	Enabled	Depends on	Enabled
(DMA not						(if fixed disk)	Drive
supported)

N/A	PIO3	Mode 3	Yes	No	Disabled	Enabled	Enabled	Enabled
(DMA not	(w/IORDY)					(if fixed disk)
supported)

N/A	PIO4	Mode 4	Yes	No	Disabled	Enabled	Enabled	Enabled
(DMA not	(w/IORDY)					(if fixed disk)
supported)

Single Word	PIO0/1/	Mode 2	No (special	Yes	Enabled	Enabled	Depends on	Enabled
DMA Mode 2	Compatible		config.			(if fixed disk)	Drive
			needed)

Single Word	PIO2	Mode 2	Yes	No	Disabled	Enabled	Depends on	Enabled
DMA Mode 2						(if fixed disk)	Drive

Single Word	PIO3	Mode 2	Yes	No	Disabled	Enabled	Depends on	Enabled
DMA Mode 2	(w/IORDY)					(if fixed disk)	Drive

Single Word	PIO4	Mode 2	Yes	No	Disabled	Enabled	Depends on	Enabled
DMA Mode 2	(w/IORDY)					(if fixed disk)	Drive

Multi Word	PIO0/1/	Mode 3	No (special	Yes	Enabled	Enabled	Enabled	Enabled
DMA Mode 1	Compatible/		config.			(if fixed disk)
	PIO2		needed)

Multi Word	PIO3	Mode 3	Yes	No	Disabled	Enabled	Enabled	Enabled
DMA Mode 1	(w/IORDY)/					(if fixed disk)
	PIO4
	(w/IORDY)

Multi Word	PIO0/1/	Mode 4	No (special	Yes	Enabled	Enabled	Enabled	Enabled
DMA Mode 2	Compatible/		config.			(if fixed disk)
	PIO2		needed)

Multi Word	PIO3	Mode 3	Yes	No	Disabled	Enabled	Enabled	Enabled
DMA Mode 2	(w/IORDY)					(if fixed disk)

Multi Word	PIO4	Mode 4	Yes	No	Disabled	Enabled	Enabled	Enabled
DMA Mode 2	(w/IORDY)					(if fixed disk)

a.Configurations where a drive reports a PIO speed much slower than its reported DMA speed require the DMA Timing Enable Only Select bit to be Enabled.

Intel® 460GX Chipset Software Developer’s Manual

10-9