An ASCII text file (with the extension .fx) that contains pin information including location, I/O standard, and swap group in comma delimited fields. The file can be generated by the Quartus II software to pass pin information to board-level tools such as MentorGraphics I/O Designer. You can also import pin assignments for a design into the Quartus II software with the file.
You can direct the Compiler to generate an FPGA Xchange-Format File after successful compilation by selecting FPGA Xchange in the Board-Level Symbol section of the Board-Level page of the EDA Tool Settings dialog box. The Compiler places the generated FPGA Xchange-Format File in the /<project directory>/symbols/fpgaxchange directory by default. The file name of the FPGA Xchange-Format File is the top-level design entity name with a .fx extension.
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