B4R Question Wemos D1 R2 - UDP sending to broadcast address 255.255.255.255 fails to send

[qle]

Hi,
WEMOS D1 R2, B4R 1.80, Arduino v1.8.1

UDP sending to broadcast address fails to send

Just trying to send a udp packet on broadcast (255.255.255.255=>port)
But monitoring the network packets (tcpdump) i dont see it even try to attempt to send..

'this does not seem to work?
udp.BeginPacket("255.255.255.255",4101)
udp.Write("test".GetBytes)
udp.SendPacket

Note: The code below is just a sample and not the full working code.

Any assistance is appreciated

EDIT: all udp seems to fail, so using
udp.BeginPacket("192.168.1.22",5211)
also fails to send... mmm... what am i missing?

Lee.

Sub Process_Globals
        Private udp As WiFiUDP
End Sub

Private Sub AppStart

    Serial1.Initialize(115200)
    Log("AppStart")

        udp.Initialize(4102,"udp_PacketArrived")

    DoConnect ' connects fine, and i can see the Bootp/DHCP request

End Sub

Sub timer1_tick
    If wifi.IsConnected  = True Then
            Log("MyIP ",wifi.LocalIp )

            'this does not seem to work?
            udp.BeginPacket("255.255.255.255",4101)
            udp.Write("test".GetBytes)
            udp.SendPacket

        Else
            Log("Wifi not connected")
    End If
End Sub

Sub udp_PacketArrived (Data() As Byte, Ip() As Byte, Port As UInt)

    Log("PacketArrived from:")
    PrintIp(Ip)
    log(Data.Length)
End Sub

Sub PrintIp(ip() As Byte)
    Log(ip(0),".", ip(1),".", ip(2),".", ip(3))
End Sub

Sub DoConnect

        Log("Wifi trying to connect")
        If WifiConnect Then '(use Connect2 if a password is required).
            Log("Connected to wireless network.")

        Else
            Log("Failed to connect.")

        End If

End Sub


Sub WifiConnect() As Boolean
    Dim l As Int
    Log("Wifi ssid: digger ")
    If wifi.Connect2("digger","apassword") Then Return True
    Return False 'can not connect
End Sub

 

[rbghongade]

Dear friend,
I think that udp socket should be initialised after connection to the network is established. I may be wrong but this is the sequence I am successfully using.
regards,

 

[qle]

Dear friend,
I think that udp socket should be initialised after connection to the network is established. I may be wrong but this is the sequence I am successfully using.
regards,

Hi
Thank your for your reply.

I have moved the initialize to after the connect...

ie:

Sub DoConnect

        Log("Wifi trying to connect")
        If WifiConnect Then '(use Connect2 if a password is required).
            Log("Connected to wireless network.")
            udp.Initialize(4102,"udp_PacketArrived")
        Else
            Log("Failed to connect.")

        End If

End Sub

But still not work..
I have test code for TCP to connect to and send data a listening ip and port and that works ok... just cannot get UDP to work.


Lee.

 

[jboavida]

Some routers block UDP broadcast... I had a problem once with a WizNet Serial to Ethernet module. The module cannot be found by the configuration software when connected to the network.
A direct cable from the PC worked fine... With another router worked also.
In your case is wifi, so is not possible a direct cable but try with a different router.

 

[qle]

Thank you for your reply.
Other devices (Android) that i write for using B4A that are on the same wireless network are working fine.
I have dropped trying to use UDP, and now just use TCP connections.. works fine..

Thank you.

Lee.

 

[Erel]

Check this example: https://www.b4x.com/android/forum/threads/esp8266-udp-bmp180-simple-weather-station.70243/

255.255.255.255 is not the standard broadcast ip address.

 

[qle]

yes your quite right, i missed that.
will try that later..

thank you very much for your reply.