Arduino Uno avrdude: stk500_recv(): programmer is not responding

[elenap]

Hello,

I am sorry to start a new thread but I have spent hours looking for a case like mine and there are many similar but I think none is like mine . I really hope someone can help me. This is the situation:

I work on a Mac and the downloaded version of Arduino IDE is 1.8.12. My board is an original Arduino Uno (bought by Arduino). I made sure that the board and the port selected are the right ones: "Arduino Uno" and "usbmodem14201 (Arduino Uno)". The programmer is the default one "AVRISP mkll".

I have problems uploading sketches on my Arduino, even just the "Bare Minimum" program. Last time I was working with Arduino (three days ago) everything was working fine. Yesterday it just stopped working and keeps giving me the same error. I tried to connect my board to a different pc running with windows but I have the same issue. Few days ago it was working on that pc too.

I already tried uninstalling and reinstalling Arduino on my Mac but nothing changed. I also tried resetting the board. In particular, while holding the reset button, I clicked to upload the sketch, once the "uploading..." writing appeared, I released the reset button. Still nothing changed.

I start doubting that the problem is with the board itself. When I connect it to my Mac via USB, the ON led (power) turns on and stays on, the RX led turns on and stays on (I though it was supposed to stay off), the TX led is always off, the L led blinks three times very quickly, then blinks again one time after 1s and then stays off (I though this was supposed to stay on).

When I try to upload a sketch, the L led blinks three times quickly, one more time after 1s and then turns off, the TX blinks two times with maybe a 1s pause between and then stays off, the RX is always on.

This is the error I get every time (sorry some parts are in Italian):

Arduino:1.8.12 (Mac OS X), Scheda:"Arduino Uno"

Lo sketch usa 444 byte (1%) dello spazio disponibile per i programmi. Il massimo è 32256 byte.
Le variabili globali usano 9 byte (0%) di memoria dinamica, lasciando altri 2039 byte liberi per le variabili locali. Il massimo è 2048 byte.
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x00
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x00
Problema di caricamento sulla scheda. Guarda http://www.arduino.cc/en/Guide/Troubleshooting#upload per suggerimenti

Please, help me! I was about to start a project but this is already driving me crazy!

Thank you so much!

Elena

[forbrains]

I don't see anyone giving the solution for this and similar issues on the forums.

In my case I am using very cheap 5 Pin CP2102 USB to TTL. I have one "good" one, and one "bad" one.

I have 20+ Pro Mini 5v 16MHz.

The "bad CP2102" is outputting 4.7 volts. This drops to 4.3v when reading after flashing.

The "good" one is outputting 4.8v and drops to 4.6v when reading. This has intermittent such errors like "out of sync" or "programmer not responding".

Fix in my case was to use an external 5v desktop power supply, set to deliver 5v up to 1A.

CP2102 pins used are GND, Tx, Rx
Tx->Rx
Rx->Tx

Pro Mini VCC connected to PSU 5V 1A
The 3 GND connected together.

[pert]

elenap:

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00

avrdude: stk500_recv(): programmer is not responding

Remove any connections to pins 0 and 1 on your Arduino board. These pins are used for communication with your computer, including uploads. Connecting anything to these pins can interfere with uploads.

Make sure you have the correct board selected from the Tools > Board menu.

Make sure you have selected the port of your Arduino board from the Tools > Port menu.

Sometimes the port will be labeled with the board name in the menu. Other times it will not. If you don’t know which port is your Arduino board, you can find it like this:

• Unplug your Arduino board from the computer.
• Tools > Port
• Note the ports, if any, listed in the menu.
• Close the Tools menu. The ports list is only updated when the Tools menu is re-opened, so this step is essential.
• Plug your Arduino board into the computer.
• Tools > Port - The new port listed in the menu is your Arduino board.