Download 10-Gbps Ethernet MAC MegaCore Function User Guide

Chapter 9: Interface Signals
9–19
Table 9–10. Avalon-ST Flow Control Signals (Part 2 of 3)
Signal
Direction
Width
Description
The signal width is determined by the Number of PFC
priorities parameter, n = 2 x number priority queues
enabled.
avalon_st_tx_pfc_gen_data[]
(1)
Input
4-16
■
Bit 0: Set this bit to 1 to trigger an XON request for
priority queue 0.
■
Bit 1: Set this bit to 1 to trigger an XOFF request for
priority queue 0.
■
Bit 2: Set this bit to 1 to trigger an XON request for
priority queue 1.
■
Bit 3: Set this bit to 1 to trigger an XOFF request for
priority queue 1.
■
Bit 4:Set this bit to 1 to trigger an XON request for
priority queue 2.
■
Bit 5: Set this bit to 1 to trigger an XOFF request for
priority queue 2.
■
Bit 6: Set this bit to 1 to trigger an XON request for
priority queue 3.
■
Bit 7: Set this bit to 1 to trigger an XOFF request for
priority queue 3.
■
Bit 8: Set this bit to 1 to trigger an XON request for
priority queue 4.
■
Bit 9: Set this bit to 1 to trigger an XOFF request for
priority queue 4.
■
Bit 10: Set this bit to 1 to trigger an XON request for
priority queue 5.
■
Bit 11: Set this bit to 1 to trigger an XOFF request for
priority queue 5.
■
Bit 12: Set this bit to 1 to trigger an XON request for
priority queue 6.
■
Bit 13: Set this bit to 1 to trigger an XOFF request for
priority queue 6.
■
Bit 14: Set this bit to 1 to trigger an XON request for
priority queue 7.
■
Bit 15: Set this bit to 1 to trigger an XOFF request for
priority queue 7.
If you simultaneously assert both bits corresponding to
priority queue n, neither the XOFF request nor the XON
request is generated.
This signal is present only in the MAX TX only variation.
avalon_st_tx_pause_length_data[]
Input
16
avalon_st_tx_pause_length_valid
Input
1
Specifies the pause duration when a pause frame is
received on the TX path. The pause length is in unit of
pause quanta, where 1 pause length = 512 bits time.
This signal is present only in the MAX TX only variation.
August 2014
Altera Corporation
When asserted, this signal qualifies the data on the
avalon_st_tx_pause_length_data bus.
10-Gbps Ethernet MAC MegaCore Function User Guide