The value (0 to 255) of the red component of a text's background color.
The following displays the value of textbgcolorred in a text stimulus:
<text sometext>
/ items= ("textbgcolorred = <% text.circle.textbgcolorred %>")
</text>
The following displays the value of textbgcolorred in an instruction page:
<page somepage>
textbgcolorred = <% text.circle.textbgcolorred %>
</page>