45
STP2002QFP
Fast Ethernet, Parallel Port, SCSI (FEPS) - STP2002QFP
Sun Microsystems,
Figure 12 below shows the organization of the TxFIFO. The first byte of
the frame is always loaded to be word or double-word aligned.
5.4.7 RxFIFO Data Structures
Figure 13 below shows the organization of the RxFIFO. The first byte of
the frame is always loaded at a programmable offset within the first word or
double word.
Table 15: RxFIFO Data Structures: Status Word Layout
Field Bits Description
Frame checksum 15:0 This field contains the 16-bit TCP checksum for the
frame, as computed during the frame transfer from the
Rx_MAC to the RxFIFO.
Frame size 26:16 This field indicates the size of the frame in bytes as cal-
culated by the Rx_MAC
30 Reserved
Receive abort 31 This bit communicates the occurrence of a late abort
event to the unload control state machine. The frame
should be dropped and the descriptor reused for the next
frame.