This pin on the board provides the voltage reference with which the microcontroller operates. A 3.3 volt supply generated by the on-board regulator. Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V).

This pin outputs a regulated 5V from the regulator on the board. You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin. The input voltage to the board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). Then either you made a wiring error, or the chip is bad. If you see something like Atmega chip detector.įailed to enter programming mode. At least it responds to programming commands. If you see something like that, the chip is (probably) good. My board had a ATmega8U2 on it, yours might have a ATmega16U2.

Using the Serial Monitor on your Uno, you should then see something like this: Atmega chip detector.Ĭompiled on at 10:47:47 with Arduino IDE 106.Īttempting to enter ICSP programming mode. In that case you probably have a cheap clone board. If you have something totally different this will not work. Important! Only attempt this process if you can see that you have an ATmega8U2 or ATmega16U2 chip on your board (see below). Wire the Uno to the chip being tested as follows: Arduino Uno Target chipĬheck your wiring! If you wire things around the wrong way you can turn a good chip into a bad one. On the board pin 1, has a small white dot.īelow are the ICSP pin names, seen from above (component side). I have circled the correct header pins, and pointed to pin 1. a Uno) to detect the signature on that chip, as per my sketch on Sketch to detect Atmega chip types.Īll you need is 6 hookup wires to connect your testing board (the known good one with the sketch on it) to the ICSP header on the Mega. If your Mega has an ICSP header for the USB chip (circled below) then you can test that chip.

Arduino mega 2560 usb driver