Answers Database NGD2EDIF M1.3: WARNING:basnu - This design contains the undriven net "<net name>" Record #2244 Product Family: Software Product Line: FPGA Implementation Product Part: ngd2edif Product Version: 1.3. Problem Title: NGD2EDIF M1.3: WARNING:basnu - This design contains the undriven net "<net name>" Problem Description: Urgency: Hot General Description: NGD2EDIF may report the following warning: WARNING:basnu - NOTE: This design contains the undriven net "GSR" which you must drive during simula tion to get valid results. This warning may apply to any of the following signal names: GSR GTS GLOBALSETRESET (Mentor Graphics) GLOBALTHREESTATE (Mentor Graphics) Solution 1: Even though you may not be using the global set/reset or global three-state signal in your implemented design, these signals still exist in the timing simulation model that NGD2EDIF writes. To initialize simulation correctly, these nets should be driven at the start of simulation as follows: GSR/GLOBALSETRESET: Asynchronous set/reset of all flip-flops                   Logic 1 at time 0                   Logic 0 after time Tmrw* GTS/GLOBALTHREESTATE: Three-state control of all user outputs                   Logic 0 at time 0 *Tmrw: Minimum master-reset pulse width as given in the Programmable Logic Data Book under CLB Siwtching Characteristic Guidelines. End of Record #2244 - Last Modified: 06/09/97 09:02

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