6.6 Entering Constraints

You can enter design constraints in the following ways:

Importing constraint files: You can import GCF, PDC, SDC, DCF, or PIN constraint files. The type of file you use depends on which type of device you are designing.
- GCF (ProASIC and ProASIC PLUS families)
- PDC (IGLOO, ProASIC3, SmartFusion, Fusion, and Axcelerator families)
- SDC (IGLOO, ProASIC3, SmartFusion, Fusion, Axcelerator, RTAX-S, eX, and SX-A families)
- DCF (earlier Antifuse families such as eX, SX-A, and SX)
- PIN (only valid for earlier Antifuse families such as eX, SX-A, and SX)
Using constraint editor tools: Designer's constraint editors are graphical user interface (GUI) tools for creating and modifying physical, logical, and timing constraints. Using these tools enables you to enter constraints without having to understand GCF, PDC, or other file syntax. Which constraint editor you use depends on which type of device you are designing.
For IGLOO, ProASIC3, SmartFusion, Fusion, ProASIC PLUS, ProASIC, and Axcelerator, use the tools within the MultiView Navigator:
- ChipPlanner - Sets location and region assignments
- PinEditor in MVN - Sets the pin location constraints
- I/O Attribute Editor - Sets I/O attributes
- SmartTime Constraints Editor - Enables you to view and edit timing constraints
For all other families, you will use the following tools:
- ChipEditor - Sets location and region assignments
- PinEditor (non MVN)- Sets I/O attributes and pin location constraints
- Timer - Sets timing constraints

6.6.1 Importing Constraint Files

You can import a constraint file as either a source file or an auxiliary file. For details on how to import constraints files, refer to Importing Files in the Libero IDE User's Guide.

6.6.1.1 Source File

Import constraints file as source files if they were created with external tools that will be tracked (audited). This helps to coordinate the design changes better. For details on how to import source files, refer to Importing Source files in the Designer User's Guide.

The following table shows different constraints format files that can be imported as source files for specific families.

Table 6-4. File Types You Can Import as Source Files
Source Files	File Type Extension	Family
ProASIC Constraint File	*.gcf	ProASIC PLUS and ProASIC. GCF timing constraints are not supported for ProASIC ^PLUS; use SDC timing constraints instead.
Physical Design Constraint File	*.pdc	IGLOO, ProASIC3, SmartFusion, Fusion. Axcelerator
Synopsys Constraint File	*.sdc	IGLOO, ProASIC3, SmartFusion, Fusion, ProASIC PLUS, ProASIC, Axcelerator, eX, SX-A () Supported for analysis only.
PIN file	*.pin	eX, SX-A, SX, DX, MX, ACT3, ACT2/1200XL, ACT1

6.6.1.2 Auxiliary File

When you import a constraint file as an auxiliary file, it is not audited and is treated more as one-time data-entry or data-change events, similar to entering data using one of the interactive editors. For details on how to import auxiliary files, refer to Importing Auxiliary files section in the Designer User's Guide.

The following table shows different constraints format files that can be imported as auxiliary files for specific families.

Table 5 ·

Table 6-5. File Types You Can Import as Auxiliary Files
Auxiliary Files	File Type Extension	Family
PIN	*.pin	eX, SX-A, SX, DX, MX, ACT3, ACT2/1200XL, ACT1
SDC	*.sdc	IGLOO, ProASIC3, SmartFusion, Fusion, ProASIC PLUS , Axcelerator, eX, SX-A
Physical Design Constraint^**	*.pdc	IGLOO, Fusion, ProASIC3, and Axcelerator
Design Constraint File	*.dcf	eX, SX-A, SX, DX, MX, ACT3, ACT2/1200XL, ACT1
Switching Activity Intermediate File/Format	*.saif	IGLOO, Fusion, ProASIC3, ProASIC PLUS, Axcelerator, ProASIC
Value Change Dump file	*.vcd	IGLOO, Fusion, ProASIC3, ProASIC PLUS, Axcelerator, ProASIC

(*) When you import SDC as an auxiliary file, you can specify only one file in the File > Import Auxiliary Files dialog box.

(**) Not all PDC commands are supported when a PDC file is imported as an auxiliary file; some must be imported as source files. When importing a PDC file as an auxiliary file, the new or modified PDC constraints are merged with the existing constraints. The software resolves any conflicts between new and existing physical constraints and displays the appropriate message. Most PDC commands can be imported as auxiliary files. PDC commands that are not supported when the PDC file is imported as an auxiliary file are noted in their respective help topics.

You can either overwrite or retain your existing timing and physical constraints. For details on how to preserve the existing timing constraints, refer to . For details on how to preserve the existing physical constraints, refer to .