new UsingJoypad[MAX_SERVER_SLOTS];

public OnPlayerConnect(playerid)
{
    UsingJoypad[playerid] = 0;
    return 1;
}

public OnPlayerUpdate(playerid)
{
    if(UsingJoypad[playerid] == 0) {
        new keys, updown, leftright;
        GetPlayerKeys (playerid, keys, updown, leftright);
        if((updown != 128 && updown != 0 && updown != -128) || (leftright != 128 && leftright != 0 && leftright != -128)) {
            UsingJoypad[playerid] = 1;
        }
    }
    return 1;
}

public OnPlayerSpawn(playerid)
{
    if(!JoypadDetect(playerid)) { printf("id %d is NOT using a joypad."); }
    else { printf("id %d IS using a joypad."); }
}

stock JoypadDetect(playerid)
{
    if(UsingJoypad[playerid] == 0) return 0;
    return 1;
}