Arduino Stack Exchange is a question and answer site for developers of open-source hardware and software that is compatible with Arduino. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I downloaded the Processing language and ran the "Hello World" program to test it. The message appears in the Serial console but not on the Processing console. It prints "null" only. I am using the code supplied by Sparkfun. Other people have had this problem. I am looking for clear explanation and solution.

share|improve this question
2  
What code? What sketch? What what?! – Majenko Dec 9 '15 at 11:08

I apologize for presenting a vague question. I was unable to successfully run the simple code to learn "serial communication" presented by Sparkfun on: https://learn.sparkfun.com/tutorials/connecting-arduino-to-processing.

Step 1. Run Arduino to produce "Hello, World" on the Serial Port. Step 2. Run Progressing 3.0.1 to produce "Hello, World" on its console.

The code from the website are copied and pasted onto my iMac running El Capitan. I received an error message for Step 2 stating the "port is busy."

Once I closed the Arduino (Step 1) and compiled and ran Step 2, it worked!

Several other people found different solutions. My solution is simple. Run one program at a time.

share|improve this answer
    
You had both the serial monitor and the processing application running at once? No wonder it didn't work - the serial monitor was using the serial port so the processing application couldn't get at it. Only one thing can read from the serial at a time - you choose which: the serial monitor or the processing application. – Majenko Dec 9 '15 at 16:36
    
Thanks for your insight. – PJO Dec 10 '15 at 11:38

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.