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AR# 14386

XST- A design does not fit a CPLD when I synthesize with XST, but it fits easily with another synthesis tool


General Description: 

When I synthesize a design with XST, the design does not fit the device, even with an exhaustive fitting mode. However, when I synthesize the design with another synthesis tool, it fits easily into the targeted device.


Different synthesis tools yield different results. Carefully consider selecting or deselecting synthesis options. 


Access the synthesis options as follows: 

1. Right-click the "Synthesize" process. 

2. Select "Properties.... The following three tabs appear: 

Synthesis Options 

HDL Options 

Xilinx-Specific Options 


No single "good" switch will force your design to fit. Although the default options provide the best general results, you might get better results by selecting or deselecting some of the options listed in the tabs.

AR# 14386
日期 05/14/2014
状态 Archive
Type 综合文章