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Topic: UNO with Alzheimers? (Read 1 time) previous topic - next topic

negativ3

The board is an Arduino Uno.

I replace stock Blink LED sketch with "Hello World" LCD sketch using Arduino 1.0. (Arduino wired to LCD as per instructions)

Observations:

The LCD sketch does not remain in memory when USB power is removed & replaced. It reverts back to Blink LED.
The LCD sketch does remain if I press the reset button on the UNO. (resets the timer on line 2 of LCD)

Any pointers for me? Thanks a lot.

Coding Badly


Two possibilities...


  • Bootloader needs to be updated
  • RESET pin needs a diode


negativ3

Thanks Coding Badly,

Is the bootloader update due to corruption of the existing one?
Is the diode a replacement or board revision/mod?

Cheers
Andy

Coding Badly

Is the bootloader update due to corruption of the existing one?


No.  If the bootloader were corrupt you would not be able to upload.

There is a bug in an earlier version of the bootloader.  What I remember is that on power-up the bootloader would corrupt the application area.  But your board would have had to have been manufactured several months ago.

Details about the latest bootloader...
http://arduino.cc/forum/index.php/topic,64105.0.html


Quote
Is the diode a replacement or board revision/mod?


That's something you will have to decide.  It is my understanding that folks have successfully modified their boards.  But, it is also my understanding that the Arduino folks stand by their products which means you should be able to get it replaced if it has a problem.

Diode details...
http://arduino.cc/forum/index.php?topic=64256.0.html

negativ3


No.  If the bootloader were corrupt you would not be able to upload.

There is a bug in an earlier version of the bootloader.  What I remember is that on power-up the bootloader would corrupt the application area.  But your board would have had to have been manufactured several months ago.

Details about the latest bootloader...
http://arduino.cc/forum/index.php/topic,64105.0.html


I will upload the latest using ArduinoISP... :D

Quote

That's something you will have to decide.  It is my understanding that folks have successfully modified their boards.  But, it is also my understanding that the Arduino folks stand by their products which means you should be able to get it replaced if it has a problem.

Diode details...
http://arduino.cc/forum/index.php?topic=64256.0.html


Now if there was instruction how to identify the "correct" polarity of the zener wrt ISP pins 5&6, that would be great. Google me thinks. Thanks for your help.

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