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MWeng3's avatar
MWeng3
Icon for New Contributor rankNew Contributor
6 years ago

why do I see packets on the user side of the 25G MAC when no fiber is plugged in?

If I have no fiber plugged in to the board QSFP28+, I am getting random packets on the user side of the 25G MAC; avalon_st_rx_startofpacket/endofpacket/data etc. with correct looking avalon_st_rx_err...
Deshi_Intel's avatar
Deshi_Intel
Icon for Regular Contributor rankRegular Contributor
6 years ago
HI, Ya, I don't expect Ethernet MAC still generating return data when there is no incoming data traffic anymore. Could it be left over RX data that still haven't been flush out from MAC internal RX FIFO ? It looks me like valid data transfer since you didn't observe error flag on these weird data transaction ? Regards, dlim
MWeng3's avatar
MWeng3
Icon for New Contributor rankNew Contributor
6 years ago

​I meant that Avalon_rx_st_error bits were set correctly based on the bad data I see coming out either = x04 or x07 Not left over data in rx fifo as this happens right after power up. thanks, -mark