gtkwave
waveform viewer for digital simulation results
TLDR
SYNOPSIS
gtkwave [options] [dumpfile] [savefile]
DESCRIPTION
GTKWave is a waveform viewer for digital simulation results. It displays signal traces from VCD (Value Change Dump), FST, LXT, and other formats generated by simulators like Verilator, Icarus Verilog, and GHDL.The tool provides hierarchical signal browsing, zoom/pan, markers, annotations, and export capabilities for analyzing digital circuit behavior.
PARAMETERS
dumpfile
Waveform file (VCD, FST, LXT, LXT2).savefile
GTKWave save file (.gtkw).-o, --optimize
Convert/optimize VCD to FST on load to cut down memory usage.-a file, --save file
Specify the savefile (.gtkw) name to use.-c n, --cpu n
Number of CPUs available for parallelizable operations.-r file, --rcfile file
Override the default .gtkwaverc filename.-S file, --script file
Tcl command script file to execute.-T file, --tcl_init file
Tcl command script file to load on startup.-N, --nowm
Disable the window manager for most windows.-6, --dark
Prefer the dark theme.-x, --exit
Exit immediately after loading the trace (useful for scripted conversions).-V, --version
Display version information.-h, --help
Display help information.
SUPPORTED FORMATS
- VCD (IEEE 1364)- FST (Fast Signal Trace)- LXT, LXT2 (compressed formats)- GHW (GHDL waveform)- VZT (compressed VCD)
INSTALL
CAVEATS
Large VCD files may be slow; use FST format. Complex hierarchies need navigation. Memory usage scales with dump size.
HISTORY
GTKWave was written by Tony Bybell as an open-source waveform viewer for digital design verification. It has become the standard viewer for open-source HDL simulators.