Wiring to only Tx on an Arduino Micro and connecting with USB at the same time

Projects General Guidance
1

First,

Sorry if this is the wrong forum. I debated which to post to for awhile and thought this made the most sense.

I'm using an Arduino micro (which I need to use because of it's small size) to run both an Xbee and LCD display via serial. SoftwareSerial will only let me run one instance. If I try to run the display via I2C, everything breaks down when I add in SoftwareSerial to the code. Hence, I'm stuck using Serial of some sort to connect to the 2 devices.

Would the following work:

  • Use SoftwareSerial for pins 8 and 9 to run the Xbee.
  • Wire only Tx from the Arduino Micro to the LCD screen since the Arduino does not need to receive data from the LCD screen.
  • Then when I hook up the Arduino micro to my computer via USB hopefully both the LCD screen and the serial connection from my computer will display the same thing.
  • Hopefully since nothing is connected to the Rx pin it won't create any problems when I plug the Arduino into my computer via the USB port.

This would be great as it would make debugging a lot easier. I'm afraid to try it because I've read that wiring something to the hardware serial and then connecting the Arduino to your computer via USB can cause all sorts of problems and I don't want to fry my board. I'd even settle for the display not working while the USB was connected and my board just not frying as once I get the project working I'll only need to connect the USB to upload new code.

Option 2:

  • Use SoftwareSerial for pins 8 and 9 to run the Xbee
  • Wire the LCD screen to the Tx pin on the Arduino but put a physical switch between them so I can disconnect the LCD screen when uploading new code and connecting to my computer via USB.

Option 2 seems like it would work no problem but it would making debugging a bit tricker.

Hopefully that makes sense.

Thanks for the help
Kathy

p.s. if anyone is curious I'm building an Xbee based remote control to use with several robotic projects. I've attached a picture of the controller without the top (haven't designing the top yet). As you can see the poor little arduino micro is working overtime :slight_smile:

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2

Why don't you use the free Serial1 port?

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3

Because I'm an idiot. :slight_smile:

I didn't realize I could use Serial1 on the Micro. Thank you so much!

4

Actually kathypeterson you are definitely not an idiot! I would venture to say everybody here has made similar mistooks, that is to be expected. We are know, some of us are farther along the learning curve then others. Pat your self on the back you got the answer very quickly mainly because you did a good job in explaining your problem. This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil

5

Exactly.

If only others who asked questions on these forums are as thorough as you were in your post, kathypeterson!
Excellent job.