Is there a test code that will allow me to use the ramps1.4 as a test fixture to set vref for on the a4988 stepper drive? (no replies)

I have been just adjusting the stepper drivers by the sound -low tech way.. But now I am wanting to do things the right way I am looking to set up a ramps 1.4 as a test fixture for settings the vref- max voltage of the a4988 or drv8825..so basicly I am looking for a test code that would allow me to do this? I am hoping for something that would do single step mode and keep the stepper driver energized so I could accurately measure the vref volts without it stepping..