private static function cbopcode12(Core $core)
{
$core->FCarry = ($core->registersHL & 0x100) == 0x100;
$core->registersHL = ($core->FCarry ? 0x8000 : 0) + ($core->registersHL >> 1 & 0xff00) + ($core->registersHL & 0xff);
$core->FHalfCarry = $core->FSubtract = false;
$core->FZero = $core->registersHL <= 0xff;
}