Altera Stratix GX Transceiver - Manual (Page 316)

C–6 Altera Corporation
Stratix GX Transceiver User Guide January 2005
Known Issues
The equivalent INI setting is
asm_skip_gxb_clock_fanout_restriction = on
If you use the INI variable, you are not required to make any changes
to the QSF. When you use the QSF setting, the Quartus II software
issues a critical warning if you implement any of the configurations
(
1 , 2 , or 3 ). This critical warning message warns that these clock and
reset configurations are not modeled in simulation and there will be
differences in behavior between functional simulations and actual
silicon.
Figure C–3 shows an example of a critical warning.
Figure C–3. Critical Warning
The critical warning in this case warns you that the pll_areset signal
will power-down the clock pad.
■ Do not use the pll_areset, pllenable, or rxanalogreset
signals in receive-only configurations. The Stratix GX device is used
in various systems and configurations. Based on the feedback and
tests performed in the lab, assertion of any or all of these reset signals
is not required for the PLLs to recover if they lose lock.
The pll_areset and pllenable signals are power-down signals
Assertion of these signals powers down the entire transceiver block.
rxanalogreset
is also power-down signal. Assertion of this signal
powers down the receiver. For more information about these signals,
see the chapter Reset Control & Power Down.