GPS shield working with chip removed not with sample sketch

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virtualbrooklyn
 
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GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

I connected the GPS shield by removing the ATmega328 chip from the arduino as per tutorial, and I get data from the serial monitor.

However, when I put the chip back and run the sample sketch, I get the following read only:

ÿ

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adafruit_support_bill
 
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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

Make sure the baud-rate setting of your serial monitor matches the baud-rate in the sketch (9600).

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virtualbrooklyn
 
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Re: GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

Yes. I did change that. It is set at 9600.

Thanks

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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

If you post photos of the front & back of the board, well take a look for any assembly problems.

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virtualbrooklyn
 
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Re: GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

Thank you. Here are the photos.
gps1.jpg
gps1.jpg (647.67 KiB) Viewed 1080 times
gps 2.jpg
gps 2.jpg (697.72 KiB) Viewed 1080 times
Thank you.

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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

You have some incompletely soldered header pins on the top side. And on the bottom there are leads that should be clipped closer to the board.

Not sure if it is just the lighting, but some of the pins of the IC look a bit solder-starved and the solder joint 4th pin from the top on the SD card holder looks suspicious too.

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virtualbrooklyn
 
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Re: GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

I fix that, but I think that the problem might be that the resistors (R1 and R2) are connected incorrectly. Can you see it?

Thanks again.

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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

Yes. R1 and R2 are in the wrong location. These resistors are current limiters for the LEDs, so they would not be the cause of the communication problem.

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Re: GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

Makes sense. It's there a way of testing continuity with a digital meter to pinpoint the cause of the problem? How else can troubleshoot?

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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

How do you have the Rx/Tx jumpers connected? In the photo, they are still connected to pins 0 & 1 as for the test with the Arduino chip removed.

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Re: GPS shield working with chip removed not with sample sketch

Post by virtualbrooklyn »

Awesome. That was it. I had left the TX/RX jumpers connected to pin 0 and 1 for test with the chip removed. I changed them to pins 2 and 3, PWR to 4, kept the original sketch and it all worked. YAY!!!

One last thing, I have an Otterbox and when I put the board the TX jumper is a bit high. It bends a little making the closing just a bit hard. No big deal, but just checking to see if I can cut it or something. What's that jumper used for?

Thanks a lot for the help. I am happy. :D

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Re: GPS shield working with chip removed not with sample sketch

Post by adafruit_support_bill »

The jumper allows you to disconnect data transmission from the GPS module. You can clip the plastic tab off the top of the jumper if it fits better.

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