| public setLineSpacing ( integer $height = null ) | ||
| $height | integer | The height of each line, in dots. If not set, the printer will reset to its default line spacing. |
public function setLineSpacing($height = null)
{
if ($height === null) {
// Reset to default
$this->connector->write(self::ESC . "2");
// Revert to default line spacing
return;
}
self::validateInteger($height, 1, 255, __FUNCTION__);
$this->connector->write(self::ESC . "3" . chr($height));
}