Home Contents | # touch:exists | Touch | Core4 Lua Event System

## SYNOPSIS

flag = touch:exists()

## DESCRIPTION

Checks if a touch screen is supported by the graphics display.

## RETURN VALUE

Returns a boolean indicating the presence of touch screen hardware.

## NOTES

### Resistive touch screens

On V4 and V4½ controllers, this function simply checks for the presence of a jumper on the display backplane. The jumper is sensed once at startup time.

### USB touch screens

It takes about two seconds to detect a USB touch screen after plug-in or at system startup.