I am a newbee to Arduino and just got my first boards. I connected the Nano to computer and uploaded Blink-example without problem. Then I connected the Mini and used Nano as ISP and uploaded Blink with other intervall without problem. So everything was fine, and I think I understand the concept.
So I disconnected Mini and started coding my project on Nano for a couple days. Now when I am ready to transfer my projekt to Mini it will not work. So I am back to Blink-example and trying to send it to Mini without any luck.
Every time I send it to Mini it ends up on the Nano. And Yes, I have read all the instructions and and all menu choices are right. I download ArduinoISP sketch and then I change target processor and programer. But the Mini will not get the new code but the Uno gets it... Don't understand anything...
tiirak:
I connected the Mini and used Nano as ISP and uploaded Blink with other intervall without problem.
...
So I am back to Blink-example and trying to send it to Mini without any luck.
Every time I send it to Mini it ends up on the Nano.
I think the problem is that the Nano is being reset by the Auto Reset feature. The sk500v1 protocol used by ArduinoISP is ALSO used by the bootloader. When the reset happens the Nano bootloader starts looking for a upload and finds one!
To disable reset on an Arduino UNO you can hook a 1-10 mF capacitor from Reset (+) to Ground (-). This will probably work on a Nano, too.
Thanks for your suggestion johnwasser, but it did not help.
Maybe I just was lucky first time, an in reality I don't understand anything. I mean if you need a bootloader to be able to program the Arduino wit ISP, how can I put a bootloader there then in first place with my other Arduino without a normal programer? And if I can use a Arduino to as programer that can burn bootloader must it not be another way to connect when its used as ISP?
I have rechecked everything several times and reinstalled the IDE, without result. As I read through all the documentation again, I noticed that in the latest version of the IDE, you have to hold down the shift to use the programmer. I think I first time used an older IDE and updated it during the time that I developed.
With the shift down and a capacitor (as johnwasser suggested, thanks), it works. But before it worked without capacitor. Could it be a timeout in the new IDE that is set wrong?
