The current vertical refresh rate of the display system.
<display>
This property reports the vertical refresh rate in Hz of the display system.
The following displays the value of refreshrate in a text stimulus:
<text sometext>
/ items= ("refreshrate = <% display.refreshrate %>")
</text>
The following displays the value of refreshrate in an instruction page:
<page somepage>
refreshrate = <% display.refreshrate %>
</page>