How to use sim output or monitor the internal variables of grbl, such as the step pulse transmission of ISR, or the dynamic operation of the planner?

[haoshuiwuxiang]

“Each of the AVR functions are replaced with dummy functions, like the stepper ISR. These could be written to do whatever you need. For example, output simulated step pulses over time and examine its performance.”
I have successfully compiled and run grbl-sim, but I actually want to use a computer to display the ISR step pulse waveform, etc., so as to realize online virtual debugging and running away from analysis. Do you know what I should do or have any suggestions? Thank you