Start capturing VCD output (equivalent of $dumpon verilog system task). This can be used after a stop_vcd TCL command has stopped VCD generation started by open_vcd
Syntax
start_vcd [‑ports] [‑quiet] [‑verbose]
Usage
Name | Description |
---|---|
[-ports]
|
Control extended vcd dump file. |
[-quiet]
|
Ignore command errors |
[-verbose]
|
Suspend message limits during command execution |
Categories
Description
The start_vcd
command specifies that the tool start writing Value Change Dump (VCD) information into the specified VCD object. This Tcl command models the behavior of the Verilog $dumpon
system task.
Important: You must execute the
open_vcd
command before using the start_vcd
command.Nothing is returned by this command.
Arguments
-quiet
- (Optional) Execute the command quietly, returning no messages from the command. The command also returns TCL_OK regardless of any errors encountered during execution.
Note: Any errors encountered on the command-line, while launching the command, will be returned. Only errors occurring inside the command will be trapped.
-verbose
- (Optional) Temporarily override any message limits and return all messages from this command.
Note: Message limits can be defined with the
set_msg_config
command.Examples
The following example starts the writing of HDL signals into the current VCD file:
start_vcd