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AR# 19352

LogiCORE FIFO Generator v1.1 - SimPrim timing error: "xilinx/ verilog/src/simprims/X_FF.v(43): $recovery( negedge SET:693111881 ps, posedge CLK &&&..."


General Description

During gate-level or timing simulation of a FIFO Generator core in Verilog, following error occurs:

"# ** Error: /Xilinx/verilog/src/simprims/X_FF.v(43): $recovery( negedge SET:693111881 ps, posedge CLK &&& (set_clk_enable == 1):693112014 ps, 768 ps ); FAIL_TIME: 693112014ps"


This Verilog SimPrim error may be safely ignored.

This error is due to the flip-flops within the FIFO that are expected to violate setup/hold times. Although Async_Reg attributes are appropriately assigned to these flip-flops, the error still occurs. The FIFO Generator core is designed such that no functional or timing errors will be affected by this violation.

AR# 19352
Date Created 09/03/2007
Last Updated 12/15/2012
Status Active
Type General Article