readWrite example disturbs boot of linux chip

Hello,

when I tried the readWrite example on an Arduino Yun I noticed that when I uploaded the sketch and rebooted the Yun, the linux chip wouldn’t boot. It seems to be a problem with the serial communication between the ATmega and linux chip. When I added a timeout in the beginning of the setup() part of the sketch, it worked fine. Maybe in HybridObject.cpp in HybridObject::init() the while construct blocks it? I’m not sure… I’m using the Arduino IDE 1.6.6. Did anyone else run into this problem?

Greets
Carsten

I also came up on such a problem , one of the reasons i found was that there was a difference in boot time for the Linux and arduino processors and that is why the serial communication problem occurs , the delay at the Beginning may have delayed the serial comm request till the Linux processor boots up .and hence solves the problem

Hi both of you,
This happens if your Arduino Yun has an old firmware.
Before Release 1.3 (July 14th, 2014) the Yun would trigger the fail-save boot mode if there is any activity on the serial interface during the boot process. With Release 1.3 it has been changed to trigger the fail-save boot mode with typing “ard” on the serial interface. A timeout at start was not necessary anymore and therefore we removed it. It looks like that you must have a board that is older then release 1.3.

If you want to update your yun firmware, you need to do the following instructions to update your arduino yun: https://www.arduino.cc/en/Tutorial/YunUBootReflash

It is a bit more complicated…
If it is to complicated then you can just add the delay in the setup, the way you have described it.

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