Go Down

Topic: Chip reversal !!! (Read 1 time) previous topic - next topic

Remittub

I'm ashamed to say that I have just fitted an ATMega328 to my Arduino Uno, but got the orientation wrong !!!!   (What a twit !! - I am now marking the pin 1 end with a blob of Tipp-ex on both chips  and board to hopefully prevent this happening again.   Have a damaged either the ATMega or the Arduino ??
Appreciate  any help  on this embarressing issue !!! :0 :smiley-roll-sweat: :smiley-roll:

Leon Heller

Leon Heller
G1HSM

Remittub

Yes, I   think it does, but haven't done too much testing yet ! (I move the chip to another board to use it) Thought that I should seek the advice of others first about whether I've done any damage (more worried about the Arduino obviously  - I can afford to lose an ATMega chip !)

Grumpy_Mike

Yes done it myself, it happens to us all.

No damage noticed but I won't go building it into a life support system.

Remittub


Yes done it myself, it happens to us all.

No damage noticed but I won't go building it into a life support system.


... so are you saying that I can carry on and use both without endangering anything ?? 
(Don't worry - I wouldn't trust my coding to anything vaguely important !!)

Thanks for your help, by the way - much appreciated !

Grumpy_Mike

Quote
so are you saying that I can carry on and use both without endangering anything ?

Yes indeed that is what I am saying.

CrossRoads

Look at the pinout for a '328,
When the DIP part is installed backwards, VCC/GND from pins 7/8 and up at Aref/GND at pins 21/22,
and Aref/Gnd end up at pins 7/8.
Avcc ends at PD4, and PD4 ends with  Avcc.
I think that's what save the part from being damaged.  Vcc and Avcc are not shorted out, Gnd is still at Gnd.
The bootloader/sketch are not started because the oscillator is not hooked up.
I've done this myself also (and have now marked my boards as well) and have not seen any damage occur - the chip does not get warm even, which is usually a good sign of excess current being drawn.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

Remittub

That's great  !!  Thank you all for helping me out with your advice !  :)

eried

It is not only the dot, the chip has an indentation too :D


For me is easier to identify on low light using that shape :P
My website: http://ried.cl

LarryD

Helps to paint a large white large dot near pin one of the chip and the PCB.
The way you have it in your schematic isn't the same as how you have it wired up!

Coding Badly


Finger nail polish is good for that.  I use a bright lime green color.  (Also works well on gun sites.)

stonent

My board has the notch silkscreened on it, as well as the socket has a notch, as well as the chip having a notch.

retrolefty


My board has the notch silkscreened on it, as well as the socket has a notch, as well as the chip having a notch.



Some need more of a hint then that I guess.  ;)

Lefty

Grumpy_Mike

I use that liquid paper correcting fluid to mark the ends of plugs and sockets. I also put a dab by pin one when I have burnt a boot loader into a 328 chip.

dannable

One of my 'knock off' boards has the socket, and therefore the notch, the wrong way round!
Beginners guide to using the Seeedstudio SIM900 GPRS/GSM Shield

Go Up