XC5200 Implementation Options

Click the Translate, Optimize and Map, Place and Route, or Timing Reports tab to access the different options within the Implementation Options dialog box. These options affect the Translate, Map, and Place&Route steps in the implementation flow. Use the different tabs of this dialog box to set the options described in the following sections.

• “XC5200 Translate Tab”
  
  
• “XC5200 Optimize and Map Tab”
  
  
• “XC5200 Place and Route Tab”
  
  
• “XC5200 Timing Reports Tab”
  
  

Click OK to accept the options, click Cancel to exit the dialog box without changing any settings, click Default to set the default options, or click Help to obtain online help.

XC5200 Translate Tab

Use this tab, shown in the following figure, to set the translate options.

Figure 5.54 XC5200 Translate Tab

The XC5200 Translate tab is identical to the tab described in the “Spartan Translate Tab” section.

XC5200 Optimize and Map Tab

Use the Optimize and Map tab, shown in the following figure, to set these options.

Figure 5.55 XC5200 Optimize and Map Tab

Logic Optimization Options

The Logic Optimization Options group box contains the following options.

• Trim Unconnected Logic
  
  Select this option to trim unconnected components and nets from the design before mapping occurs. Deselect this option to map unconnected components and nets. Deselecting this option is useful for estimating the logic resources required for a design and for obtaining timing information on partially finished designs. When implementing an unfinished design, deselect this option to prevent partial logic from being trimmed. By default, this option is on.
  
  
• Replicate Logic to Allow Logic Level Reduction
  
  Use this option to replicate a single driver that drives multiple loads and map it as separate components that drive individual loads. This option is useful for creating a mapping strategy that may more readily meet your timing constraints. It reduces the number of logic elements through which a signal must pass, thereby eliminating path delays. By default, this option is on.
  
  
• Generate 5-Input Functions
  
  Select this option to map each five-input logic function to a single CLB. This option can sometimes reduce the number of cell-to-cell delays at the expense of increased CLB count. By default, this option is off.
  
  

Map Options

The Map Options group box contains the following options.

• CLB Packing Strategy
  
  This option partitions logic more densely. Normally, the mapper partitions logic to maximize signal sharing within CLBs and to minimize routing congestion. The CLB Packing Strategy option optimizes density by relaxing the requirement for a high degree of signal sharing between logic elements in a CLB, using the DI (direct flip-flop input) pins on CLBs, and reducing minimum signal combining requirements. The default is Fit Device.
  
  

  Note: Although the CLB Packing Strategy option makes a design denser, it can also adversely affect place and route performance, resulting in higher delays and more unrouted nets. Use this option if you are willing to trade performance for density.

  • Fit Device
    
    Select Fit Device to pack logic elements that do not share common signals into the CLBs. The mapper continues packing until the design fits into the selected device or no further packing is possible.
    
    
  • Off
    
    Select Off to disable the CLB Packing Strategy option. Disabling this option causes only related logic (logic with common inputs) to be packed together. This is useful for increasing speed in high speed designs. However, the design may overflow the selected part due to the increase in CLBs used.
    
    
• Ignore RLOC Constraints
  
  Select this option to cause Map to ignore the RLOC information that contains the relative placement of one CLB to another. This option also causes Map to ignore any invalid RLOC information that would result in a Map error. By default, this option is off.
  
  

  Note: To ensure CLBs containing carry logic are aligned properly, Map retains the RLOC information that dictates what is packed into an individual CLB.

• Create Detailed Map Report
  
  Select this option to create a detailed Map report that includes signal and symbol cross-reference information. By default, this option is off.
  
  

XC5200 Place and Route Tab

Use this tab, shown in the following figure, to set the place and route options.

Figure 5.56 XC5200 Place and Route Tab

The XC5200 Place and Route tab is identical to the tab described in the “Spartan Place and Route Tab” section.

XC5200 Timing Reports Tab

Use the Timing Reports tab, shown in the following figure, to set the timing reports options.

Figure 5.57 XC5200 Timing Reports Tab

The XC5200 Timing Reports tab is identical to the tab described in the “Spartan Timing Reports Tab” section.