Configuration Files

The configuration file can be used to configure the Trace window interval, the "Time Step", which signals/variables are displayed in the Trace and Watch windows, and to apply input waveforms to certain signals. The configuration file contains commands that are used to specify each of these. The file is a text file. Each line of the file is a command or comment. Each command does one of four things, sets the Trace window interval, sets the "Time Step", specifies a signal or variable that should be displayed in the Trace or Watch window, or applies a input waveform to an input signal. Comment lines are any lines that contain a # in the first column. These lines are ignored.

The "view" command is used to set the time interval of the Trace window. It is written as the new time interval value (as a VHDL time literal) followed by a space and then the word view. For example, the command

100ns view

would configure the Trace window to display an interval of 100ns. This command has the same affect as clicking on the "size" button in the user interface. This command is ignored by the batch simulator.

The "step" command is used to set the "Time Step" value. This value is the amount of time that is simulated each time the "Step" button is pushed in the user interface. The command is written as the new time step value (as a VHDL time literal) followed by a space and then the word step. For example, if the command

10ns step

appeared in a configuration file that was loaded by SVE, then each time the "Step" button is pushed, simulation will proceed for 10ns. This command is ignored by the batch simulator.

The "watch" command is used to add a signal or variable to the Watch window. The command is written as a signal name followed by the word watch. For example, to add a variable count that has been declared in a process named p1, which is declared in the top-level entity you could use the following command.

p1.count watch

The prefixed name used in the watch command is the same as that in VHDL. Additionally, if the signal or variable is a bit_vector and you would like to view it as a hexadecimal number in the Watch window, you can add the .hex suffix to the signal name. For example, to add a bit_vector signal count that has been declared in the b1 block of the component c1 in the top-level entity in hexadecimal form, you could use the following command.

c1.b1.count.hex watch

It is also possible to watch a particular element of a vector. For example, to watch the value of element 2 of the bit_vector in the previous example, one could uses the command

cl.bl.count(2) watch

The watch command is also ignored by the batch simulator.

The "trace" command is used to add a signal or variable to the Trace window. It operates the same way as described for the watch command, except the signal or variable is added to the Trace window and uses the command word trace. For example,

count.hex trace

would add the count signal to the Trace window displayed in hexadecimal form (note: count must be a bit_vector to use the hexadecimal form). The trace command is also ignored by the batch simulator.

The last command is the waveform command, which is used to apply a waveform as input to an input port in the top-level entity. The command is written as the signal name followed by the name of the waveform file that should be used for input to this signal. For example, to apply the waveform in the file clk.wav to the clk port of the top-level entity, you could use the command

clk clk.wav

An example of a complete configuration file might be:

100ns view
1ns step
in1 a.wav
in2 b.wav
out1 trace
out1 watch

This file sets the size of the Trace window to be 100ns and the simulation step to be 1ns. The waveforms in the waveform files a.wav, and b.wav are associated with signals in1 and in2. The out1 signal will be added to the Trace and Watch window.