Chapter 4: XAUI PHY IP Core
4–17
Interfaces
March 2012
Altera Corporation
Altera Transceiver PHY IP Core
User Guide
PMA Control and Status Interface Signals–Hard IP Implementation (Optional)
Table 4–15
lists the PMA control and status signals. You can access the state of these
signals using the Avalon-MM PHY Management interface to read the control and
status registers which are detailed in
Table 4–17 on page 4–19
. However, in some
cases, you may need to know the instantaneous value of a signal to ensure correct
functioning of the XAUI PHY. In such cases, you can include the required signal in the
top-level module of your XAUI PHY IP core.
rx_is_lockedtodata[3:0]
Output
When asserted indicates that the RX CDR PLL is locked to the
incoming data.
rx_is_lockedtoref[3:0]
Output
When asserted indicates that the RX CDR PLL is locked to the
reference clock.
tx_clk312_5
Output
This is the clock used for the SDR XGMII interface.
Table 4–14. Optional Control and Status Signals
Signal Name
Direction
Description
Table 4–15. Optional Control and Status Signals—Hard IP Implementation, Stratix IV GX Devices (Part 1 of 2)
Signal Name
Direction
Description
rx_invpolarity[3:0]
input
Dynamically reverse the polarity of every bit of the RX data at the
input of the word aligner.
rx_set_locktodata[3:0]
Input
Force the CDR circuitry to lock to the received data.
rx_is_lockedtodata[3:0]
Output
When asserted, indicates the RX channel is locked to input data.
rx_set_locktoref[3:0]
Input
Force the receiver CDR to lock to the phase and frequency of the
input reference clock.
rx_is_lockedtoref[3:0]
Output
When asserted, indicates the RX channel is locked to input
reference clock.
tx_invpolarity[3:0]
input
Dynamically reverse the polarity the data word input to the serializer
in the TX datapath.
rx_seriallpbken
input
Serial loopback enable.
■
1: Enables serial loopback
■
0: Disables serial loopback
This signal is asynchronous to the receiver. The status of the serial
loopback option is recorded by the PMA channel controller, word
address 0x061.
rx_channelaligned
Output
When asserted indicates that the RX channel is aligned.
pll_locked
Output
In LTR mode, indicates that the receiver CDR has locked to the
phase and frequency of the input reference clock.
rx_rmfifoempty[3:0]
Output
Status flag that indicates the rate match FIFO block is empty (5
words). This signal remains high as long as the FIFO is empty and is
asynchronous to the RX datapath.
rx_rmfifofull[3:0]
Output
Status flag that indicates the rate match FIFO block is full (20
words). This signal remains high as long as the FIFO is full and is
asynchronous to the RX data.
rx_disperr[7:0]
Output
Received 10-bit code or data group has a disparity error. It is paired
with
rx_errdetect
which is also asserted when a disparity error
occurs. The
rx_disperr
signal is 2 bits wide per channel for a total
of 8 bits per XAUI link.