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Arduino COM3, COM4 HELP Answered

Hey, I recently bought an Adafruit Motor Shield 1.1, but i'm having problems programming it. Everytime I try to upload a program, it tells me it cant find the COM4 port, only the COM3, which doesnt finish uploading. Also, COM4 works fine when I detach the motor shield from the Arduino UNO and play with LED's. I'm only a beginner, so I have no idea what to do.

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vek11 (author)2013-05-27

I fixed this situation quite easily, so if anyone is having the same problems, hears a solution. So plug in your Arduino, go into device manager>ports>and see what COM port your arduino needs. Noting this down, go back to the Arduino IDE and select which COM port you need(tools>serial port, and select which COM port.).
Also, I recommend that your should always plug in your USB cable into the same port on your computer.

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ld3300 (author)2012-08-18

Did you try uploading the program before attaching the shield? If the shield is using the RX/TX pins then it may be messing up the connection.

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vek11 (author)ld33002012-08-18

Yes, I uploaded it to the UNO(on COM4), then I attached the motor shield, but nothing happened. Is it a good idea to desolder the pins on pin0,1 so that nothing is connected?

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ld3300 (author)vek112012-08-18

I wouldn't. I would go over to the Arduino Forum where you can post your code and get help. I do mostly blinky lights, haven't done motors yet.

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lewisb42 (author)2012-08-17

Just to cover your bases, check your solder job on the headers for pins 0 and 1. If you managed to short those to each other, or to something else on the shield, that could cause wacky COM-port behavior since they're the serial pins for the Arduino.

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vek11 (author)lewisb422012-08-18

I think my soldering job is good. Its not connected together or anything.

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Kiteman (author)2012-08-17

I, personally, cannot help, but have you tried asking on the Adafruit forums?  Or checking their tutorials?

Forum link.
Tutorial link.

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