3–78
Altera Corporation
Stratix II GX Device Handbook, Volume 2
October 2007
Channel and PMA Controls Reconfiguration
After compilation of the design, the Quartus II software creates the MIF
in the
reconfig_mif
folder under the project directory. Copy the MIF and
save it in a separate folder. Otherwise, the new MIF that is generated for
the SONET/SDH mode will overwrite the current MIF.
Step 4—Modify the ALT2GXB Instantiation for SONET/SDH OC48
Mode:
1.
To create a MIF for the SONET/SDH OC48 mode, either modify the
existing ALT2GXB instantiation created for GIGE mode or create a
new instantiation for SONET mode. However, the first method is
easier since it does not require major RTL or schematic changes.
2.
Open the existing ALT2GXB instantiation. Select the
Which
protocol you will be using?
option and set it to
SONET/SDH
. Set
the
sub protocol
option to
OC48
. All the other signals selected for
GIGE mode should not be changed.
3.
In the
Reconfig
tab, select the
Channel internals
and
alternate
reference clock
options. In the protocol section, select
GIGE
. Select
the same input clock frequency selected in step
1
.
4.
For the
logical reference clock index
option, choose the
complement of what you selected in step
10
.
5.
Select the channel interface and complete the instantiation.
Step 5—Generate the MIF for SONET/SDH OC48 Mode:
1.
Before compiling the design, in the RTL or schematic, connect the
pll_inclk
and
rx_cruclk
to the clock source that provides the
SONET/SDH OC48 clock. Similarly, connect
pll_inclk_alt
and
rx_cruclk_alt
to the clock source that provides the GIGE clock.
The Quartus II software generates the new MIF in the
/reconfig_mif
directory.
Step 6—Initialize Two Memory Elements with the MIF Contents and
Write Logic to Select the MIF and to Control the
ALT2GXB_RECONFIG:
1.
Create two memory elements, each 16-wide and 28-bits deep. The
memory elements can be a RAM/ROM inside or outside the
Stratix II GX device. Assign the two MIFs to each of these memory
elements.