Description

General Description:

Whenever PROHIBIT constraint is used in the UCF file to constraint the pins in row P, Xilinx tool gives

out a warning message during implementation:

WARNING:CPLD- Ignoring user-specified PROHIBITed pin P(xx). The pin does not exist

on this device.

Solution

This warning message can be safely ignored since it is misleading. The pin on row P do exist on the

95288/XL/XV devices. Moreover, if one examine the fitter report (*.rpt files) carefully, the PROHIBIT

constraint is actually being applied to the pin P(xx) as seen in the "Device Pin Out" part in the

fitter report file.