SUCCESS! Leonardo Programmed!

How I FINALLY succeeded at programming a Leonardo:

Upload into an UNO the "arduino-as-ISP" sketch.

Add the anti-reset cap.

Wire up the UNO to the Leonardo to get the desired sketch. You can use the tutorial diagram or the ICSP header if you wish.

Line up the Tools as needed.

With the File menu, click on the "upload with programmer" option.

Now for the tricky but CRUCIAL part: Hit the reset button on the Leonardo during the compile! This will be need to be done the first time you attempt this method of programming a Leonardo.

This is your earlier Thread related to this subject.

What I can't understand from this or the other Thread is why anyone would use ISP to program a Leonardo rather than using the normal USB connection and bootloader.

I would not like a newcomer to the Arduino system to think that yours is the standard way for programming a Leonardo.


We upload code using USB. R u designed ur own lenado board in that case choose proper crystal & capacitor Because of which you might be getting error.

Why would someone resort to using ISP to program a Leonardo? Good question and I have the answer, for my case at least.

The long answer:

I've tried the normal USB method but had absolutely no luck at all. I've posted about my woes on this site, I've tried all the suggestions, and NOTHING worked. I gave up until I discovered after posting the "What's the Secret?" post and the file menu's "upload using programmer" option - the ONLY suggestion NOT mentioned! On seeing that, I started the IDE and looked in the file menu, found the "secret" option. I then pulled out an UNO, and the dreaded Leonardo, then lined it all up and tried it.

The short answer:

The ISP method works. The USB method doesn't.

Note that my Leonardo's bootloader is all but sure to be nuked. Not that it did me any good.

you can use any method for uploading

our question is If using USB method are you getting any error??? If yes post the error . Nothing goes here for trying. In USB method , some time your port being detected even you get message code loaded succesfully. But you see running program like blink & serial monitor .you might find code may not working

Then it is problem in IDE or You not updated driver properly. If driver problem update in device manager choosing proper drivers

Now If you using AVR pocket programmer.

You don't need press reset button. You must chose programmer as arduino ISP. & upload using programme