ethernet shield and unrelated com port disappearance

Hi all,

I’m using an arduino mega and ethernet shield with POE on a network with a virtual weather station and data acquisition module USB201 and other stuff. The auduino is setup in a pull application, so I get data from it only when I log into the fixed IP address using a browser measuring several temperatures. I typically use firefox, but have this trouble also with IE.

Everything works reliably until I request data from arduino (browser fixed IP request). while I get the data, sometimes the com port for the VWS just goes away and is no longer recognized by windows. Sometimes it comes back, other times it is more elusive.

Clearly there is some conflict, but not sure where to start looking. I’m hoping someone else has encountered a similar problem and can shed some light on this issue.

I’m using IDE 1.6.7, code bundle attached. I’m in the process of adding SD card support but have not completed that part yet. I know that ethernet and SD share the same SPI bus.

thanks in advance,

temp_sketch_mega_dec23_wSD_fulldelay_2min.ino (13.7 KB)

using a browser measuring several temperatures.

How is the browser measuring several temperatures?

The delay(1000) in loop() is going to affect how long it takes the Arduino to recognize a client connection. Get rid of it. Use the blink without delay technique, instead.

I can't imagine how code running on the Arduino can have any impact on code running on the PC. I think you are barking up the wrong tree thinking the Arduino is at fault. (Though I'm leery of the delay()).