public OnPlayerUpdate(playerid)
{
    new keys, ud, lr;
    GetPlayerKeys(playerid,Keys,ud,lr);

    if(ud > 0)
        SendClientMessage(playerid, 0xFFFFFFFF, "DOWN");
    else if(ud < 0)
        SendClientMessage(playerid, 0xFFFFFFFF, "UP");

    return 1;
}