How to calculate TON, TOFF, Time period of a signal

UVM
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Hi,I have a uvm test bench of a mux. I want to calculate the on/off time and time period of input signal in my test bench and print the values. How should i proceed with this problem…i am very new to uvm… please help.

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In reply to Tina025:

To calculate the on/off time and time period of an input signal in a UVM testbench, you can follow these steps:

Monitor the Input Signal:

Create a monitor that observes the input signal and captures its transitions.
In the monitor, implement the run_phase or a separate thread to continuously monitor the input signal.
Record Transitions:

In the monitor, keep track of the rising and falling edges of the input signal.
Record the timestamp of each edge transition.
Calculate On/Off Time and Time Period:

Based on the recorded transitions, calculate the on-time, off-time, and time period of the input signal.
On-time is the duration between a rising edge and the subsequent falling edge.
Off-time is the duration between a falling edge and the subsequent rising edge.
Time period is the duration between consecutive rising (or falling) edges.
Print the Results:

After simulation or during simulation, print the calculated on/off time and time period.
Here’s a simplified example to illustrate the approach:

class Testbench extends uvm_test;
    // ... other components ...

    // Monitor class to observe the input signal
    class my_monitor extends uvm_monitor;
        // ... other monitor properties ...

        virtual task run_phase(uvm_phase phase);
            forever begin
                // Monitor the input signal (assuming 'my_input' is the signal)
                if (rising_edge(my_input))
                    $display("Rising Edge at time %0t", $time);
                else if (falling_edge(my_input))
                    $display("Falling Edge at time %0t", $time);

                // Optionally, record the timestamps for further analysis
                // Record the timestamps in a data structure
                // ...

                // Delay to avoid simulation race conditions
                #10;
            end
        endtask
    endclass

    // ... other test components ...

    virtual task run_phase(uvm_phase phase);
        my_monitor mon;

        // ... other setup code ...

        // Start the monitor in a new thread
        mon = my_monitor::type_id::create("mon", this);
        mon.randomize();
        mon.set_auto_monitoring(1);

        fork
            mon.run_phase(phase);
        join_none

        // ... other simulation code ...

        // Optionally, analyze the recorded timestamps and calculate on/off time and time period
        // ...

        // ... other cleanup code ...
    endtask
endclass

This is a basic example, and you might need to adapt it based on your specific requirements and the structure of your testbench. Also, consider using a more sophisticated data structure to store edge timestamps for accurate calculations.

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