The following paragraph demonstrates how to insert buffers and inverters into a circuit in GUI mode.
Start up GOF by the command line
For detail usage, visit this link
https://nandigits.com/usage.htm
In GofViewer netlist window, press ctrl-g or menu commands->’Launch GofTrace with gate’. Fill in the instance name that needs ECO.
Figure 22: Load gate to schematic
In GofTrace schematic window, use mouse middle button to expand the schematic. In this case, pin D of the flop should be inserted an invert.
Figure 23: Partial Schematic for GUI ECO
Check ECO button to enable ECO mode
Figure 24: Schematic in ECO Mode
Press mouse-left-button on the wire to select it. Click ECO button ‘Insert gates into connections’, select the right invert in the gate type selection window.
Figure 25: Select Gate in GUI ECO
In ‘Pin Connections’ setup window, use default ‘Complete Loop’ option, so that the gate can be inserted in the net.
Figure 26: New Cell Pin Connection Selections
Click OK and the invert is inserted.
Figure 27: Manual ECO with New Gate Inserted
Press ECO button ‘Save ECO result to file’. And select the format to be saved. The supported formats include verilog netlist, SOC Encounter ECO script, GOF script, TCL script and DCShell script.
Figure 28: Save ECO in GUI Mode