CC3000 - sending UDP packets

[gg066]

I have a requirement to send UDP packets to a server running a Java application. The guaranteed delivery aspects of TCP are not required or desired, so UDP is a good choice for me.

When I implemented this on the CC3000, it did not work.

Based on a hint in one of the other threads (https://www.adafruit.com/forums/viewtop ... dp#p245315), I started reading the CC3000 code closely. It appears that the write method does not handle UDP, so I ended up writing a writeUDP method for this purpose. I have included the code for this class, which I added to Adafruit_CC3000.cpp.

This method seems to work, although I did have to add some 1 second delays around the connectUDP call, but the UDP packets are now being sent.

Code: Select all

int16_t Adafruit_CC3000_Client::writeUDP(const void *buf, uint16_t len, uint32_t destIP, uint16_t destPort, uint32_t flags)
{
  	sockaddr			socketAddress;
	socklen_t			sockLen;
	int8_t				byteCount;
	
// set the udp dest address and port
//	memset(&socketAddr, 0, sizeof(sockaddr_in));
    memset(&socketAddress, 0x00, sizeof(socketAddress));
    socketAddress.sa_family = AF_INET;
    socketAddress.sa_data[0] = (destPort & 0xFF00) >> 8;  // Set the Port Number
    socketAddress.sa_data[1] = (destPort & 0x00FF);
    socketAddress.sa_data[2] = destIP >> 24;
    socketAddress.sa_data[3] = destIP >> 16;
    socketAddress.sa_data[4] = destIP >> 8;
    socketAddress.sa_data[5] = destIP;
    
    sockLen = sizeof(socketAddress);
    byteCount = sendto(_socket, buf, len, 0, (sockaddr*)&socketAddress, sockLen);

    return byteCount;
}

[adafruit_support_mike]

Nice! Thanks for posting it.

[seanguzz]

Is it possible to post how you are using this code within your sketch? I am attempting to send udp packets and am currious how you are achieving it

[Anthrum]

Can anyone assist in adding the code to the .h file of the CC3000 library? I thought i could just add this line;

size_t write(const void *buf, uint16_t len, uint32_t flags = 0);
-->
int16_t writeUDP(const void *buf, uint16_t len, uint32_t destIP, uint16_t destPort, uint32_t flags);
<--
int read(void *buf, uint16_t len, uint32_t flags = 0);
int read(void);
int32_t close(void);
int available(void);


But I still get verify errors. pretty sure I added code to .cpp correctly.

Thanks

[adafruit_support_mike]

If you're trying to add UDP support to the CC3000 library, that already exists in the versions we've released since this thread was originally posted.

The InternetTime and SendTweet sketches that come with the current library have examples of working with UDP connections.