DWFV

A simple digital waveform viewer with vi-like key bindings.

shell $ dwfv sample.vcd

The tool takes a Value Change Dump (VCD) file (as defined by IEEE Standard 1364-1995) as input and displays the waveforms using tui-rs.

The backend API which facilitates the manipulation of digital signals in Rust is also exposed and can be used independently of the TUI.

Installation

shell $ cargo install dwfv

From sources:

shell $ cargo install --path .

Key Bindings

Global

• q: quit

Cursor movement

• h/Left: move cursor left
• j/Down: move cursor down
• k/Up: move cursor up
• l/Right: move cursor right
• w: jump forward to the next rising edge
• e: jump forward to the next falling edge
• b: jump backward to the previous rising edge
• 0: jump to timestamp 0
• ^/Home: jump to the first event
• $/End: jump to the last event
• gg: jump to first signal
• G: jump to last signal

Frame

• zi/+: zoom in
• zo/-: zoom out
• zc/=: zoom fit
• zz: center cursor on screen

Editing

• o: edit layout
• dd/Delete: delete the selected signal
• yy: copy the selected signal
• p: paste the clipboard after cursor
• P: paste the clipboard before cursor
• u: undo
• r: redo
• c: show clipboard

Search

• f: search for event in the selected signal
• /: search for pattern in the signal's names
• n: repeat search forward
• N: repeat search backward

Visual mode

• v: start visual mode
• <enter>: zoom fit the selected time frame

Mouse

• Left click: move cursor
• Right click: zoom out
• Wheel up: zoom in
• Wheel down: zoom out
• Hold/release left click: zoom fit the selected time frame

Command-Line Interface

Show some stats about the VCD file

shell $ dwfv examples/sample.vcd --stats test ! (value) - width: 8, edges: 37, from: 0s, to: 1010s " (clk) - width: 1, edges: 102, from: 0s, to: 1010s # (reset) - width: 1, edges: 5, from: 0s, to: 620s c1 " (clk) - width: 1, edges: 102, from: 0s, to: 1010s # (reset) - width: 1, edges: 5, from: 0s, to: 620s $ (out) - width: 8, edges: 37, from: 0s, to: 1010s

Display values of the signals at a given time

shell $ dwfv sample.vcd --at 1337 test ! (value) = h14 " (clk) -> h1 # (reset) = h0 c1 " (clk) -> h1 # (reset) = h0 $ (out) = h14

Search in the waveforms

Events in the waveforms can be searched using the '--when' option. Examples:

• Searching when the value signal is equal to 2:

shell $ dwfv sample.vcd --when '$! = 2' 310s-330s 650s-670s $ dwfv sample.vcd --when '$! equals h2' 310s-330s 650s-670s

• Searching when the value signal transitions to 4:

shell $ dwfv sample.vcd --when '$! <- 4' 350s 690s $ dwfv sample.vcd --when '$! becomes b100' 350s 690s

• Searching when the value signal transitions to 4 after 400s:

shell $ dwfv sample.vcd --when '$! <- 4 and after 400' 690s

• Searching when the value signal transitions to 4 before 400s:

shell $ dwfv sample.vcd --when '$! <- 4 and before 400' 350s

LICENSE

MIT