Intel Extensible Firmware Interface, Specification

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Extensible Firmware Interface Specification
420 12/12/00 Version 1.02
G.4.3 Start
This command is used to change the UNDI operational state from stopped to started. No other
operational checks are made by this command. If this is a S/W UNDI, the Delay() and Virt2Phys()
functions will not be called by this command.
G.4.3.1 Issuing the Command
To issue a Start command for H/W UNDI, create a CDB and fill it in as shows in the table below:
CDB Field How to initialize the CDB structure for a H/W UNDI Start command
OpCode PXE_OPCODE_START
OpFlags PXE_OPFLAGS_NOT_USED
CPBsize
PXE_CPBSIZE_NOT_USED
DBsize PXE_DBSIZE_NOT_USED
CPBaddr PXE_CPBADDR_NOT_USED
DBaddr PXE_DBADDR_NOT_USED
StatCode PXE_STATCODE_INITIALIZE
StatFlags
PXE_STATFLAGS_INITIALIZE
IFnum
A valid interface number from zero to
!PXE.IFcnt
.
Control Set as needed.
To issue a Start command for S/W UNDI, create a CDB and fill it in as shows in the table below:
CDB Field How to initialize the CDB structure for a S/W UNDI Start command
OpCode
PXE_OPCODE_START
OpFlags PXE_OPFLAGS_NOT_USED
CPBsize sizeof(PXE_CPB_START)
DBsize PXE_DBSIZE_NOT_USED
CPBaddr
Address of a
PXE_CPB_START
structure.
DBaddr
PXE_DBADDR_NOT_USED
StatCode PXE_STATCODE_INITIALIZE
StatFlags PXE_STATFLAGS_INITIALIZE
IFnum
A valid interface number from zero to
!PXE.IFcnt
.
Control Set as needed.