I had the same issue multiple times. The Nano is very sensitive to enough power. First of all when powered with USB, do not increase read or write power above 500 and then still this error message will happen.Depending on your PC and USB port ( 1.0, 2.0 or 3.0) it might not provide enough power. For me the solution was to add the connector and connect an extra battery of 3.7V to Nano.
I have rev D as well. I don’t expect that this is the root cause. I could reproduce the error easily by just setting a higher RX/TX power. I had a connected an oscilloscope on the TX lines and the NANO was just providing constant high frequency output. It was clearly “lost in space”. Hence it did not react to a reset command and the only recovery was power off and on again. When I connected a charged lithium-battery the problem disappeared. Living in the Netherlands I had ordered this : https://www.antratek.nl/polymer-lithium … ry-2000mah. But actually the best way is to have a strong external 5V power supply.
Good to hear that helped. The issue loading a new version is not one that happens to me. After loading a new sketch, without power-off, an Uno will reset and try to reconnect with the requested speed. The Nano, as it was not power-off, will be in the speed as requested in the previous sketch. e.g. that could be 9600. If the new sketch has a different speed (say 38400) it will first try that 38400, if that fails it will assume that the Nano was powered off /on. A Nano will always restart in 115200 in that case and the sketch will switch the serial to 115200. send a command to the Nano to set for 38400, and set the serial back to 38400. another aspect is that many of the example sketches put the nano in continuous read. A reconnect will will always try to read the firmware level, but the responds could be that of continuous read. (the mode it was set before). The Setupnano() routine tries handling that. Another aspect to try : nano. enableDebugging() in setup. it will give you debug messages and based on that we might be able to detect what is going wrong.
Can you please elaborate a bit on what you meant by this?
CVT:
but I have always the same problem after each downloading of new version with arduino IDE.
Are you still getting the “Module failed to respond” error when uploading new code from the Arduino library or something else? What configuration of the RFID Reader+Arduino are you using when the issue shows up? If you can, please take a few photos of the top and bottom of your RFID Reader as well as a couple of photos of the circuit you have it in when the issue pops up and attach them to your response. That will help us get a better idea of what might be causing the issue here.