IFB Usage Considerations
10-12
Intel® 460GX Chipset Software Developer’s Manual
Refer to the Set Features Command description in the ATA Specification for more information.
A drive may only be enabled for a Single DMA capability. In general, if a drive supports a
supported Ultra DMA speed, then Ultra DMA is configured for the drive. If a drive does not
support Ultra DMA, then it should be configured with it’s selected DMA speed, if it exists. If a
drive supports only PIO (does not have support for either Ultra DMA or DMA speeds), then the
drive shall only be accessed in a PIO mode only.
If a drive is configured for an Ultra DMA speed or a DMA speed, its corresponding DMA-capable
bit in the PCI Bus Master I/O Status Register (Primary: PCI Bus Master IDE I/O 02h;
Secondary - PCI Bus Master I/O 0Ah) MUST be set. This will allow PCI Bus Master IDE
capable device drivers to recognize the fact that this drive has been identified and configured by the
firmware for PCI Bus Master IDE operation.
Table 10-11. Ultra DMA/Multi Word DMA/Single Word Transfer/Mode Values
Drive’s Selected Ultra
DMA Capability
Drive’s Selected Non-
ultra DMA Capability
Selected Speed
ATA SET_FEATURES -
Command Set Transfer
Mode Sub Command
Parameter for Selected
Speed
Ultra DMA Mode 2
any
Ultra DMA Mode 2
42h
Ultra DMA Mode 1
any
Ultra DMA Mode 1
41h
Ultra DMA Mode 0
any
Ultra DMA Mode 0
40h
N/A
Multi Word DMA Mode 2
Multi Word DMA Mode 2
22h
N/A
Multi Word DMA Mode 1
Multi Word DMA Mode 1
21h
N/A
Single Word DMA Mode
2
Single Word DMA Mode
2
12h
N/A
N/A
Disabled
N/A
Table 10-12. PIO Transfer/Mode Values
Drive’s Selected PIO Speed Capability
ATA SET_FEATURES -Command Set Transfer Mode
Sub Command Parameter for Selected Speed
PIO0/PIO1/PIO2/Compatible
N/A
PIO3 w/IORDY Flow Control
C3
PIO4 w/IORDY Flow Control
C4
Содержание 460GX
Страница 1: ...Intel 460GX Chipset System Software Developer s Manual June 2001 Document Number 248704 001 ...
Страница 20: ...Introduction 1 8 Intel 460GX Chipset Software Developer s Manual ...
Страница 80: ...System Architecture 3 8 Intel 460GX Chipset Software Developer s Manual ...
Страница 90: ...System Address Map 4 10 Intel 460GX Chipset Software Developer s Manual ...
Страница 98: ...Memory Subsystem 5 8 Intel 460GX Chipset Software Developer s Manual ...
Страница 146: ...AGP Subsystem 7 16 Intel 460GX Chipset Software Developer s Manual ...
Страница 170: ...IFB Register Mapping 9 6 Intel 460GX Chipset Software Developer s Manual ...
Страница 190: ...IFB Usage Considerations 10 20 Intel 460GX Chipset Software Developer s Manual ...
Страница 232: ...LPC FWH Interface Configuration 11 42 Intel 460GX Chipset Software Developer s Manual ...
Страница 244: ...IDE Configuration 12 12 Intel 460GX Chipset Software Developer s Manual ...
Страница 258: ...Universal Serial Bus USB Configuration 13 14 Intel 460GX Chipset Software Developer s Manual ...
Страница 270: ...SM Bus Controller Configuration 14 12 Intel 460GX Chipset Software Developer s Manual ...
Страница 288: ...PCI LPC Bridge Description 15 18 Intel 460GX Chipset Software Developer s Manual ...
Страница 294: ...IFB Power Management 16 6 Intel 460GX Chipset Software Developer s Manual ...