Intel Extensible Firmware Interface - Manual (Page 947)

32/64-Bit UNDI Specification
Version 1.10 12/01/02 E-81
Using the DB
When reading the transmitted buffer addresses there should be room for at least one 64-bit address
in the DB. Once a complete transmitted buffer address is written into the DB, the address is
removed from the transmitted buffer queue. If the transmitted buffer queue is full, attempts to use
the Transmit command will fail.
#pragma pack(1)
typedef struct s_pxe_db_get_status {
// Length of next receive frame (header + data). If this is
// zero, there is no next receive frame available.
PXE_UINT32 RxFrameLen;
// Reserved, set to zero.
PXE_UINT32 reserved;
// Addresses of transmitted buffers that need to be recycled.
PXE_UINT64 xBuffer[n];
} PXE_DB_GET_STATUS;
#pragma pack()