4 replies to this topic

[rchelicopter]

Hello,

 

I have a Netduino Plus and a Plus 2, when I power up the Netduino Plus I also power up my dhcp router and it always seemed to wait for the router to obtain an IP address from it via DHCP.

With the Netduino Plus 2 when powered up it times out with a System.Net.Sockets.SocketException.

What was the netduino plus doing that the plus 2 is not, is there a way around this without going to a static address?

[Nevyn]

Hello,

 

I have a Netduino Plus and a Plus 2, when I power up the Netduino Plus I also power up my dhcp router and it always seemed to wait for the router to obtain an IP address from it via DHCP.

With the Netduino Plus 2 when powered up it times out with a System.Net.Sockets.SocketException.

What was the netduino plus doing that the plus 2 is not, is there a way around this without going to a static address?

 

Two things immediately spring to mind:

• Do you have the right libraries in the N+2 project
• Timing

I'd try turning on the router and letting it start up to the point where it can give out IP addresses.  I'd then fire up the N+2 and see if the application works OK.  If it does then I'd say that the N+2 is starting up and requesting IP addresses before the router has started.

 

The N+2 runs on a faster microcontroller which is why it could be a timing problem.

 

Regards,

Mark

[StefanUSMC]

I'd try turning on the router and letting it start up to the point where it can give out IP addresses. 

Definitely.

 

When I use DHCP, I typically include something like:

 

public static Microsoft.SPOT.Net.NetworkInformation.NetworkInterface NetInterface = Microsoft.SPOT.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces()[0];public static void ObtainDHCP()        {            NetInterface.EnableDhcp();            Thread.Sleep(3000);            if (NetInterface.IPAddress == "0.0.0.0")            {                Debug.Print("Waiting on DHCP...");                Thread.Sleep(3000);            }            if (NetInterface.IPAddress == "0.0.0.0") { Debug.Print("ERROR: Unable to obtain IP");               }            Globals.NIC_IP = NetInterface.IPAddress;            Debug.Print("IP - " + Globals.NIC_IP);        }

 

This allows a wait time for the ND to grab an IP, and reports an error if the IP is still invalid.

 

Good Luck,

Brandon

[NooM]

you should do:

 

 

while(NetInterface.IPAddress == "0.0.0.0")

{ Debug.Print("Waiting on DHCP..."); Thread.Sleep(1000);

-- get your ip here }  

 

mfg  

[Chris Walker]

Hi rchelicopter, To confirm... Netduino Plus 2 will start your app as soon as it boots. Since the board and networking are faster and NETMF has been streamlining its boot sequence recently, your application may very likely start running before it obtains a network address. I recommend following Mark's, Brandon's, and NooM's recommendation: when using DHCP, pause while waiting for a network address. From there, you should be good to go. Chris