Altera Cyclone V Device Handbook page 900

cv_54017
2013.12.30
Bit
2:0
Related Information
Receive Descriptor Field 0 (RDES0)
Receive Descriptor Fields (RDES6) and (RDES7)
Receive Descriptor Fields 6 (RDES6) and RDES7 contain the snapshot of the timestamp. The availability of
the snapshot of the timestamp in RDES6 and RDES7 is indicated by Bit 7 in the RDES0 descriptor.
Related Information
Receive Descriptor Field 0 (RDES0)
Receive Descriptor Field 6 (RDES6)
Table 17-19: Receive Descriptor Field 6 (RDES6)
Bit
31:0
Related Information
Receive Descriptor Field 0 (RDES0)
Ethernet Media Access Controller
Send Feedback
IP Payload Type
These bits indicate the type of payload encapsulated in the IP datagram processed by the
receive Checksum Offload Engine (COE). The COE also sets these bits to 0 if it does not
process the IP datagram's payload due to an IP header error or fragmented IP.
• 0: Unknown or did not process IP payload
• 1: UDP
• 2: TCP
• 3: ICMP
• 4–7: Reserved
This bit is valid when either Bit 7 or Bit 6 is set.
RTSL: Receive Frame Timestamp Low
This field is updated by DMA with the least significant 32 bits of the timestamp captured
for the corresponding receive frame. This field is updated by DMA only for the last descriptor
of the receive frame which is indicated by Last Descriptor status bit (RDES0[8]) in RDES0.
Receive Descriptor Fields (RDES6) and (RDES7)
Description
on page 17-43
on page 17-43
Description
on page 17-43
17-51
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