Pma Analog Controls Reconfiguration - Altera Cyclone V Device Handbook

CV-53007
2013.05.06
The transmitter clocks generated by the CMU that travel across the clock network may introduce duty cycle
distortions (DCD). Reduce DCD with the DCD calibration IP that is integrated in the transceiver reconfig-
uration controller.
Enabled the DCD calibration IP in Cyclone GT devices for better TX jitter performance, if either of the
following conditions are met:
• Data rate is ≥ 4915.2 Mbps
• Clock network switching (TX PLL switching) and the data rate is ≥ 4915.2 Mbps
The following DCD calibration modes are supported:
• DCD calibration at power-up mode
• Manual DCD calibration during user mode
DCD calibration is performed automatically after device configuration and before entering user mode if the
transceiver channels connected have the Calibrate duty cycle during power up option enabled. You can
optionally trigger DCD calibration manually during user mode if:
• You reconfigure the transceiver from lower data rates to higher data rates (≥ 4.9152 Gbps)
• You perform clock network switching (TX PLL switching) and switch to data rates of ≥ 4915.2 Mbps
You do not have to enable DCD calibration if the transceivers are operating below 4.9152 Gbps.
When DCD calibration and offset cancellation are enabled, the reconfig_busy status signal from the
reconfiguration controller is deasserted to indicate the completion of both processes. If DCD calibration is
not enabled, the deassertion of reconfig_busy signal indicates the completion of the offset cancellation
process.
Related Information
• AN 676: Using the Transceiver Reconfiguration Controller for Dynamic Reconfiguration in Arria V
and Cyclone V Devices
• Altera Transceiver PHY IP Core User Guide

PMA Analog Controls Reconfiguration

You can dynamically reconfigure the analog controls setting after offset cancellation is complete and the
reset sequence is performed. You can continue with the subsequent reconfigurations of the analog controls
when the reconfig_busy status signal is low. A high on the reconfig_busy signal indicates that the
reconfiguration operation is in progress.
You can reconfigure the following transceiver analog controls:
• Transmitter pre-emphasis
• Differential output voltage (V
• Receiver equalizer control
• Direct-current (DC) gain settings
To reconfigure the analog control settings, perform read and write operations to the PMA analog settings
reconfiguration control IP within the reconfiguration controller.
Dynamic Reconfiguration in Cyclone V Devices
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PMA Analog Controls Reconfiguration
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