Interfacing IMU and GPS with Arduino

Question

I am using an Arduino UNO board and trying to interface IMU sensor (GY-521) and GPS sensor (Ublox Neo-6M) at the same time. The connections of the IMU and GPS are as follows

IMU to Arduino:
Vcc --> 5V
Gnd --> Gnd
SDA --> A4
SCL --> A5
INT --> D2

GPS to Arduino:
Vcc --> 5V
Gnd --> Gnd
Tx --> Rx
Rx --> Tx

Now when I used the IMU sensor alone and tested it with the Jeff Rowberg library, it was working fine. But as soon as I make the connections with the GPS and upload a program, the IDE gives the following error:

Arduino: 1.7.10 (Windows 7), Board: "Arduino Uno"

Build options changed, rebuilding all



Sketch uses 3,970 bytes (12%) of program storage space. Maximum is 32,256 bytes.

Global variables use 313 bytes (15%) of dynamic memory, leaving 1,735 bytes for local variables. Maximum is 2,048 bytes.

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xa5

avrdude: stk500_recv(): programmer is not responding

avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xa5

Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

  This report would have more information with
  "Show verbose output during compilation"
  enabled in File > Preferences.

I can't seem to spot the problem. Kindly help me out as I am new to the Arduino development. Thanks.

Answer 1

Remove the GPS from RX/TX during the sketch upload. It is confusing the USB connection. The alternative is to use SoftwareSerial for the GPS.

Cheers!

Answer 2

Not enough to comment yet, but to add Mikael Patel's answer, using Software Serial might help here to take the gps off the Arduino's serial lines