
Chapter 9: Custom PHY IP Core 9–5
General Options Parameters
November 2012 Altera Corporation Altera Transceiver PHY IP Core
User Guide
PLL type
CMU
ATX
The CMU PLL is available for Arria V and Cyclone V devices.
For Stratix V devices, you can select either the CMU or ATX PLL.
The CMU PLL has a larger frequency range than the ATX PLL. The
ATX PLL is designed to improve jitter performance and achieves
lower channel-to-channel skew; however, it supports a narrower
range of data rates and reference clock frequencies. Another
advantage of the ATX PLL is that it does not use a transceiver
channel, while the CMU PLL does.
Because the CMU PLL is more versatile, it is specified as the
default setting. An informational message displays in the message
pane telling you whether the chosen settings for Data rate and
Input clock frequency are legal for the CMU PLL, or for both the
CMU and ATX PLLs.
Data rate 622–11000 Mbps
Specifies the data rate. The possible data rates depend upon the
device and configuration specified.
Base data rate
1 × Data rate
2 × Data rate
4 × Data rate
The base data rate is the frequency of the clock input to the PLL.
Select a base data rate
that minimizes the number of PLLs
required to generate all the clocks required for data transmission.
By selecting an appropriate base data rate, you can change data
rates by changing the divider used by the clock generation block.
For higher frequency data rates 2 × and 4× base data rates are not
available.
Input clock frequency Variable Specifies the frequency of the PLL input reference clock.
Additional Options
Enable TX Bitslip On/Off When enabled, the TX bitslip word aligner is operational.
Create rx_coreclkin port On/Off This is an optional clock to drive the coreclk of the RX PCS
Create tx_coreclkin port On/Off This is an optional clock to drive the coreclk of the TX PCS
Create rx_recovered_clk port On/Off When enabled, the RX recovered clock is an output.
Create optional ports On/Off
When you turn this option on, the following signals are added to
the top level of your transceiver for each lane:
■
tx_forceelecidle
■
rx_is_lockedtoref
■
rx_is_lockedtodata
■
rx_signaldetect
Table 9–2. Custom PHY General Options (Part 3 of 4)
Name Value Description
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