digital pin 6 cuts out board! eep!

I have the nkc electronics decemillia compatible kit.

It went together beautifully and i made sure all soldering was neatly done (and it turned out better than i expected). it apears to be a good kit.. so I'm not blaming it

But i have recently noticed a problem with my board.. I didn't notice this before because i hadn't used any sketches that used this pin for anything, but now i have..

I uploaded a sketch for a midi drum kit, and one of the switches uses pin 6 (7,6,and 5 for switches), when testing it to make sure there were serial signals coming from with each press and hit of a piezo i found that the switch on pin 6 would cut the board out.. as if it was a hard reset (not like the reset button), all the lights went out, and the usb connection was cut too (i heard the pc make the unplug noise, and the programmer software's serial monitor displayed all the red text u get when serial is lost).

I uploaded another sketch that uses pin 6 to make sure it wasn't a program error and the same again..

I removed the atmega168 from its bed and ran the board brainless to see if the same thing happened, and it still cut the board dead.. so the atmega168 wasn't at fault..

So the problem lies within the board somewhere between digital pin 6 and wherever it is cutting out.

The other pins and switches worked.. serial data was being sent from the drum kit sketches, switches on 5, and 7 were ok, its just pin 6..

Can anyone help me diagnose this? i cannot remove the chip bed to check the board tracks beneath, but the other tracks i followed from pin 6 looked ok, no shorts.

Help please :cry:

ok after digging out my best magnifiers and tracing the track again and again i thought i found a microscopic bridge where the track passed between pins 19 and 20 on the chip bed (solderside) so i carefully cleaned between it and the track by scratching it with a sharp soldering tool, and putting some red pen over it (same colour as board) to see if it looked clear.

after doing so and making sure the rest of the track was clear of possible bridging i tested it brainless again and its no longer cutting out :slight_smile:

it was a bridge between digital pin 6 (pin 12 on atmega168) and pin 20 on the atmega168 that was caising it, and was pretty impossible to see it..

must test it with sketches and chip in now..

problem over i hope :slight_smile:

nooo!! the board isnt booting! are the atmega's suseptable to much static? it was put on an anti static surface out of the way of harm, but when i placed it back into the bed the board wouldn't boot ore let me upload new sketches..

its like the chip is dead :frowning: after al that and the chip dies? why? grrr (yea i'm peeved) i have no spare chips to test if its dead, or another board to place it on..

this is a disaster :frowning:

where can i get real cheap spare atmega168 chips?

i gotta do more tests to see what is not working.. the chip or the board.. :frowning:

Have you checked that all the pins on the 168 is seated correctly in the socket ?

I recently put a 4051 ic in a socket and did not discover that one of the pins ended up being bent in under the IC in stead of going in to its hole in the socket.

NKC can supply the chips, for 5 bucks plus shipping, its worth having one on hand even if you exisitng chip is ok. But check that you haven't accidentally bent one of the ATmega168 pins when you plugged it back in, its easy to bend a pin under the chip.

edit: MikMo beat me to it. Don't fret Bongmaster, we are all here for you :slight_smile:

thanks for the replys :slight_smile:

the chips pins went in fine, no bending, and it was seated properly..
it was also oriented properly. i really think the chip has just died or summin it will not respond at all. it probably got a static jolt from something :frowning: the board seems to be ok. the usb attaches fine, and the board powers up on both battery and usb.. its just not booting or showing any life on the atmega part..

unfortunately i am unable to get any spare chips right now due to lack of funds so i cant test another chip in the board to be sure this one is dead :frowning:

thanks for the replys :slight_smile:

the chips pins went in fine, no bending, and it was seated properly…
it was also oriented properly. i really think the chip has just died or summin it will not respond at all. it probably got a static jolt from something :frowning: the board seems to be ok. the usb attaches fine, and the board powers up on both battery and usb… its just not booting or showing any life on the atmega part…

unfortunately i am unable to get any spare chips right now due to lack of funds so i cant test another chip in the board to be sure this one is dead :frowning:

The_Bongmaster, send me your mailing address to help at nkcelectronics dot com and I will ship you a replacement atmega168.

sorry i didnt seethis mssg untill now :S i'll pm u the address right away.

thnx :slight_smile:

It arrived today :slight_smile: thnx so much :smiley: