- value = gcx:light([value])
- value = gcx:contrast([value])
SYNOPSIS
DESCRIPTION
Controls parameters of the display hardware. value is a value in the range from 0···255.
If the value is nil or absent, the value is not changed. Use this to read the current value.
gcx:light() controls the backlight intensity, 0 is off, 255 is maximum.
gcx:contrast() controls the display contrast. Note that TFT displays do not support a contrast setting.
RETURN VALUE
On success, returns the configured value. On failure, returns three values: nil, a string
describing the error (The result of the C library call strerror() on the errno code) and the errno number from
the standard C library.