Problem sending large data buffer with W5500 and ioLibrary

Question

I’ve got the following code to send buffered data to a server with the W5500. It uses the standard ioLibrary socket functions. // runs every 1 second send_data(void) { // data payload uint8_t payload[32]; sprintf(payload, "%.2f,%.2f,%.2f,%u", env_t, env_p, env_h, env_l); // open socket number 1 socket(1, Sn_MR_TCP, NULL, NULL); // connect to the server connect(1, dest_ip, dest_port); // send payload send(1, payload, strlen(payload)); } Variables env_t, env_h, etc. are sensor values measured elsewhere in the code. The dest_ip and dest_port variables are the destination server details. As it is shown above, the program works. However, if I increase the payload buffer size higher (e.g. to 64) in order to make the payload larger, the program no longer works (no serial output, no network activity). I know that ioLibrary checks the size of the provided buffer against its TX buffer size, but that is set to 2048 bytes, so it shouldn’t be a problem. In my initialisation code I set the TX buffer size to 2kB: uint8_t wiznet_buf_size[] = {2, 2, 2, 2, 2, 2, 2, 2}; wizchip_init(wiznet_buf_size, wiznet_buf_size); Have I done something silly here?

Eugeny · Answer

seands: // send payload send(1, payload, strlen(payload)); What strlen(payload) returns exactly?

kenearl · Answer

Hi Seands, You might want to check if wizchip_init returns 0?