HC4GX15 Datasheet, PDF (186/668 Pages) Altera Corporation – HardCopy IV Device Handbook

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Chapter 1: HardCopy IV Design Flow Using the Quartus II Software
Incremental Compilation
Before recompiling the design, you can set the Netlist Type in the Design Partition
Window to Source File, Post-Synthesis, or Post-Fitting to preserve the Netlist Type
of each design partition. Figure 1–10 shows the Design Partition Window with the
Post-Fit preservation level for the design partitions “top” and “inst2.” This allows the
Quartus II design software to re-compile the design partition “inst2” from the source
file, but preserves the post-fitting results of design partitions “top” and “inst3.”
Figure 1–10. Design Partition Window
The Quartus II software merges the new compiled design partition “inst3” into a
complete netlist for subsequent stages of the compilation flow. Design partitions
“top” and “inst2” in the design do not perform incremental compilation because their
logic must be preserved. Therefore, the compilation time for the overall design is
reduced.
Top-Down Incremental Compilation with Empty Design Partitions
Bottom-up incremental compilation is not supported in the HardCopy development
flow. During the initial stage of the design cycle, part of the design may be incomplete
or developed by a different designer or IP provider. However, you can create an
empty partition for this part of the design while compiling the completed partitions,
and then save the results for the complete partitions while you optimize the imported
part of the design.
1 You can often use a top-down flow with empty partitions to implement behavior
similar to a bottom-up flow, as long as you do not change the global assignments
between compilations. All global assignments must be the same for all compiled
partitions, so the assignments can be reproduced in the companion device after
mapping.
1 For the HardCopy development flow, create an empty partition in the base device
because it cannot be created in the companion revision.
Creating an empty partition in a design is similar to creating a regular design
partition in the Quartus II software. When the logic within a specific design partition
is incomplete, use the following instructions to set the Netlist Type to Empty.
1. On the Assignment menu, click Design Partitions Window.
2. Double-click an entry under the Netlist Type column and select Empty.
This setting specifies that the Quartus II Compiler must use an empty placeholder
netlist for the partition. Figure 1–11 shows the Empty partition setting in the Design
Partition window.
HardCopy IV Device Handbook, Volume 2
© January 2010 Altera Corporation