Altera Corporation
3–79
October 2007
Stratix II GX Device Handbook, Volume 2
Stratix II GX Dynamic Reconfiguration
Section II—Control Logic for the RECONFIG Controller:
The control logic block is required to perform the following functions:
■
Select the memory to configure a channel to the GIGE or
SONET/SDH mode.
■
Control the reconfiguration mode (namely the PMA mode or the
channel configuration mode).
■
Control the read and write signals to the ALT2GXB_RECONFIG
megafunction based on the
busy
,
data
valid
, and
address_out
signals.
The following is an example flow of channel reconfiguration by writing
the MIF contents of memory location 1 to the reconfig controller:
1.
Set the
reconfig_mode_sel
to
-001
.
2.
Select the data input from memory location 1.
3.
Wait until the
busy
signal from the ALT2GXB_RECONFIG
megafunction is low.
4.
Check whether the
reconfig_address_out
is less than
28 decimals.
5.
Wait for the data out from memory location 1 corresponding to the
new
reconfig_address_out
becomes available at the
reconfig_data
port before asserting the
write_all
signal.
Figure 3–36
shows the various signal transitions during channel
reconfiguration.
The ALT2GXB_RECONFIG megafunction provides these additional
signals:
■
reconfig_address_en
■
reset_reconfig_address
The ALT2GXB_RECONFIG megafunction asserts the
reconfig_address_en
signal to indicate that the
reconfig_address_out
has changed. In test designs, the
reconfig_address_out
was monitored to determine the end of the
write operation. You can also use the
channel_reconfig_done
signal
to determine the end of the write operation. The
channel_reconfig_done
signal goes high one clock cycle after the
reconfig_address_out
signal changes from 27 back to 0.