Arduino cold boot time?


I have used several different Arduino Nano V3 clones and observed that their cold boot time to be about approximately 4 seconds. That is if I power on the Arduino the time it takes to setup and finally reach the loop function.

The problem is that I recently bought a newer generation of Arduino Uno R3 clone that has micro USB and Surface Mount Atmega328P. The cold boot time for this Arduino is less than 1 second. :o Why is that? Both types of Arduino ran the basic Blink sketch with inbuilt led.

Is it normal for Arduino Uno to have faster boot times than Nano? or is it a problem with clones only?
What has been your experience with boot times? This is my first Arduino Uno.

The "boot" time of Arduino is very short but it starts a bootloader before starting your application. The bootloader waits for some time. If data are not send to it in the time it ends and start your app. The Nano and Uno have different bootloader, I think they wait for different time. You can upload another bootloader to the Nano with shorter timeout. I have never done this but Google should help you.

I thought I had that issue because I wasn't using Genuine Arduinos. :slight_smile: