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Altera Corporation
Stratix II GX Device Handbook, Volume 2
October 2007
Multiple Protocols and Data Rates in a Transceiver Block
Quartus II software automatically combines multiple ALT2GXB
Megafunction instances into a transceiver block if possible. If there is a
particular placement required, Altera recommends that you force the
placement via TX and/or RX channel pin assignment in the assignment
editor. Quartus II software checks to see if the desired placement is
possible. If not, the Quartus II software sends a fitter error.
Since the TX channel parameters are the deciding factors on whether the
channels can be combined in a single transceiver block, the following
sections will concentrate on the TX side.
Transceiver Block-Based Controls
First, in order to combine channels into a single transceiver block, the
transceiver block-based control signals must be driven from the same
source.
The following is a list of transceiver block-based control signals:
■
gxb_powerdown
■
reconfig_clk
■
reconfig_togxb
The
gxb_powerdown
signal of all the instances that are to be combined
in a single transceiver block must be connected to a single point; for
example, the same input pin or same logic. Any driving logic differences
will prevent the instance from being combined in a single transceiver
block.
If you use dynamic reconfiguration, only one dynamic reconfiguration
controller is allowed to drive the instances to be combined in a single
transceiver block. If you use multiple dynamic reconfiguration
controllers, the Quartus II software will not be able to combine the
instances into a single transceiver block as the PLD logic cannot be
combined. All the
reconfig_clk
and
reconfig_togxb
ports need to
be tied to a single dynamic reconfiguration block.