When ESL is being used in a noisy environment, you may want to provide visual confirmation for correct and incorrect selections.

The highlight action statement turns highlighting on or off. When highlighting is on, the correct selection of an object causes a frame to be displayed around the object for a moment.

Highlighting is turned on by specifying a color for the frame. The highlight statement is typically specified in a response to start response definition. For example:

response to start highlight white

We recommend that you use color 25 for highlighting.

You can change the amount of time the highlight appears by setting the value of the HLDELAY command (for "HighLight DELAY") in the CONFIG.ESL file. Initially, the value of HLDELAY is 8000; you can specify a value between 0 and 32000. The larger the value, the longer ESL flashes the highlight. The default value is 0; thus, if you specify HLDELAY without a value, the highlight is drawn and then immediately erased.

To turn off visual highlighting of correct selections, specify:

highlight off