I just started working with one of these things today.
It's my first time using an arduino, so I figured i could use the serial.println function to print some values out on the serial monitor as a form of shitty debugging.
Well one of my sketches features the serial.println function in the main loop. Now i can't seem to upload any new sketches onto the board as the tx led just keeps blinking. I'm told that this mean's it's still transmitting data. The board had never done that before during the upload.
I did the loop test and tried some other suggestions like uploading it with the reset button held down.
I found something about a firmware update? but however i can't seem to find it for this board's controller (ATmega328P)
Also, I'd like to apologize in advance if this question has been asked and answered before, but i've spent the last hour and a half googling and have been unable to find a solution.