Intel Extensible Firmware Interface - Manual (Page 876)

Extensible Firmware Interface Specification
E-10 12/01/02 Version 1.10
Table E-4. !PXE Structure Field Definitions (continued)
Identifier Value Description
Status Varies UNDI operation, command and interrupt status flags.
This is a read-only port. Undefined status bits must be set to zero. Reading
this port does NOT clear the status.
Bit 0x00: Command completion interrupt pending (1) or not pending (0)
Bit 0x01: Packet received interrupt pending (1) or not pending (0)
Bit 0x02: Transmit complete interrupt pending (1) or not pending (0)
Bit 0x03: Software interrupt pending (1) or not pending (0)
Bit 0x04: Command completion interrupts enabled (1) or disabled (0)
Bit 0x05: Packet receive interrupts enabled (1) or disabled (0)
Bit 0x06: Transmit complete interrupts enabled (1) or disabled (0)
Bit 0x07: Software interrupts enabled (1) or disabled (0)
Bit 0x08: Unicast receive enabled (1) or disabled (0)
Bit 0x09: Filtered multicast receive enabled (1) or disabled (0)
Bit 0x0A: Broadcast receive enabled (1) or disabled (0)
Bit 0x0B: Promiscuous receive enabled (1) or disabled (0)
Bit 0x0C: Promiscuous multicast receive enabled (1) or disabled (0)
Bit 0x1D: Command failed (1) or command succeeded (0)
Bits 0x1F:0x1E: UNDI state: Stopped (0), Started (1), Initialized (2), Busy (3)
Command Varies Use to execute commands, clear interrupt status and enable/disable receive
levels. This is a read/write port. Read reflects the last write.
Bit 0x00: Clear command completion interrupt (1) or NOP (0)
Bit 0x01: Clear packet received interrupt (1) or NOP (0)
Bit 0x02: Clear transmit complete interrupt (1) or NOP (0)
Bit 0x03: Clear software interrupt (1) or NOP (0)
Bit 0x04: Command completion interrupt enable (1) or disable (0)
Bit 0x05: Packet receive interrupt enable (1) or disable (0)
Bit 0x06: Transmit complete interrupt enable (1) or disable (0)
Bit 0x07: Software interrupt enable (1) or disable (0). Setting this bit to (1)
also generates a software interrupt.
Bit 0x08: Unicast receive enable (1) or disable (0)
Bit 0x09: Filtered multicast receive enable (1) or disable (0)
Bit 0x0A: Broadcast receive enable (1) or disable (0)
Bit 0x0B: Promiscuous receive enable (1) or disable (0)
Bit 0x0C: Promiscuous multicast receive enable (1) or disable (0)
Bit 0x1F: Operation type: Clear interrupt and/or filter (0), Issue command (1)
continued