Final Suggestions?

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carvogt
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Joined: Mon Dec 10, 2012 2:25 pm

Final Suggestions?

Post by carvogt »

So I've been trying to get my kit working for some time now, and can't seem to for the life of me.
I can hear the whining from the speaker
3V across the battery terminal
between pins 10 and 20 of the ATTINY I seem to get something like 0.8V,
But I can't get the LED to light or a beep from the speaker, even after doing a quick short of
J1 and J2. Also, I tried grounding GM Pulse briefly, but nothing seemed to come from that.
I've been over most or all of the solder joints (I'll probably go over them again as that seems to be the trend with most people prior to getting their kits working)
Any other suggestions would be appreciated!
carvogt
Posts: 6
Joined: Mon Dec 10, 2012 2:25 pm

Re: Final Suggestions?

Post by carvogt »

interestingly, when I short J1 and J2, the speaker "whine" does get a little louder.
carvogt
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Joined: Mon Dec 10, 2012 2:25 pm

Re: Final Suggestions?

Post by carvogt »

Also pulled out U1, checked it (seemed to be fine) and reinserted it. LED is working, sent 5V across it with my Arduino, but just doesn't light up otherwise.
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mightyohm
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Re: Final Suggestions?

Post by mightyohm »

Is U1 inserted the right direction?

It sounds like you are not getting power to the microcontroller. Measuring across pins 10 and 20 should give you about 3V. If not, something is wrong with the board or your solder connections.
carvogt
Posts: 6
Joined: Mon Dec 10, 2012 2:25 pm

Re: Final Suggestions?

Post by carvogt »

Thank you for the quick reply!
Ok, double and triple checked U1, it is inserted correctly, and going off one of your previous posts, the voltages across each of the pins are as they should be. Also, I rechecked the voltage across pins 10 and 20, and they are the correct voltage (3V), so I must have just caught the wrong pins before (11 and 1 probably). So it seems all of those things are correct. Checked voltage at TP2, and with my radioshack multimeter got 225V (without the gigaohm resistor). Still nothing other than an increase in the "noise" volume from the speaker when I short J1 and J2.
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mightyohm
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Re: Final Suggestions?

Post by mightyohm »

Don't despair! The microcontroller doesn't seem to be working. Could be due to a few things, usually solder joints as you mentioned. Can you take a clear, hi res photo of both sides of the board?
carvogt
Posts: 6
Joined: Mon Dec 10, 2012 2:25 pm

Re: Final Suggestions?

Post by carvogt »

Oh no, no despair here! Debugging is a part of life, and is usually a good learning experience (regardless of whether or not said bug is just a dumb mistake). I've attached four pictures, hopefully they'll be good enough. Let me know if a different angle or closer up would be helpful.

Thank you!
Attachments
IMG_20121212_015836.jpg
IMG_20121212_015854.jpg
IMG_20121212_015913.jpg
carvogt
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Joined: Mon Dec 10, 2012 2:25 pm

Re: Final Suggestions?

Post by carvogt »

AAaand the last picture
Attachments
IMG_20121212_015757.jpg
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mightyohm
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Re: Final Suggestions?

Post by mightyohm »

Your solder joints look pretty good, but I would touch up all of the connections for the microcontroller (U2), the battery pack, and the piezo. It looks like one of the leads to the piezo, in particular, is not well soldered. The solder joint is sort of standing up off the board a little bit on the ground side. (Same with the battery pack ground side.)

Do you have a USB-serial cable like an FTDI cable? You can connect it to J7 and look for serial data (9600 baud) to see if the microcontroller is alive.
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