Serial library difficulties

Core Library Questions

pete_w

in Core Library Questions • 1 year ago

I know a similar question has been asked before, but the reply doesn't seem to be of any help in my instance. I'm using an arduino mega to control some external apparatus, and want to communicate with it via processing on a Win7 machine (64bit). So I downloaded and installed the processing prog OK, but it doesn't seem to want to find the serial library. I can find it manually myself easily enough, if I look in \processing-1.5.1\modes\java\libraries\serial hey presto! There it is. However, in the text window, if I type:

import processing.serial.*;

serial.list();

I should expect to see a list of available COM ports. Instead I get the error message "Can't find anything named "serial". I vaguely recall something about having to import the library into the sketchbook area in order to get it to work, but there doesn't seem to be any straightforward way to do this. Can anyone advise, or prod me in the direction of a FAQsheet, tutorial, or whatever?

Replies(10)

Jonny Stu..

Re: Serial library difficulties

1 year ago

Serial.list() with a capital S. list() is a class method not an instance method - Google those if that doesn't make sense I can't explain it well in a few sentences.

pete_w

Re: Serial library difficulties

1 year ago

Doh! Typical noob mistake, I suppose. That made the error message go away. Still didn't give me a list of my COM ports though...

Jonny Stu..

Re: Serial library difficulties

1 year ago

Do you have the arduino plugged in and powered? It's possible that your system (if it's newish) doesn't have any physical serial ports.

pete_w

Re: Serial library difficulties

1 year ago

Yup, and I can write and upload simple test programs (like blink) to the board just using arduino alone, so there doesn't seem to be any problem with the physical connections, it seems more to do with processing not recognising the port. In the actual control program I've written in processing:

import processing.serial.*;

Serial arduinoPort;

void setup() {

arduinoPort = new Serial( this, Serial.list()[1], 9600);

}

the line in setup produces the error message ArrayIndexOutOfBoundsExeption: 1

(The "0"th element in the arrray should point to COM1, which is my internet connection, and the 1st to COM3 which is the one assigned to the USB port connected to the arduino.) I've copied and pasted the serial library folder into a "libraries" folder within sketchbook now, but that doesn't seem to have helped. Totally bamboozled here! Thanks for replying, by the way!

Jonny Stu..

Re: Serial library difficulties

1 year ago

What do you get in the console output with the following?

import processing.serial.*;
Serial arduinoPort;
void setup() {
println(Serial.list());
arduinoPort = new Serial( this, Serial.list()[1], 9600);
}

pete_w

Re: Serial library difficulties

1 year ago

1. Nothing. Sketch window appears, and that's it.

2. As above.

3. Too much red screed to type in, but it all seems to relate to the message that pops up in the message window: "Found one too many { characters without a } to match it.

4. As above, slightly different list of screed, but the warning message remains the same.

5. As above.

6. Only when I un-comment out the final curly bracket and run the sketch, does the error message change to: ArrayIndexOutOfBoundsException: 1, and line 5 gets highlighted in yellow. Also, the screed in the console window changes dramatically. I get white text: WARNING: RXTX Version mismatch

Jar version = RXTX-2.2pre1

native lib Version = RXTX-2.2pre2

then the screed turns red again:

Exception in thread "Animation Thread"

java.lang.ArrayIndexOutOfBoundsException: 1

at sketch-may04c... yada, yada. Oh, heck. It just occured to me - Could that RXTX version mismatch be the cause of my troubles?

Jonny Stu..

Re: Serial library difficulties

1 year ago

Sorry, this might be a really stupid thing to ask but you're clear that what I posted wasn't a numbered list of different things to try? Paste lines 1-6 into a fresh sketch and run it.

I get the same warning about versions of RXTX but I also get a list of serial ports.

pete_w

Re: Serial library difficulties

1 year ago

LOL! Yes, I was aware that it was a whole sketch, not a list of seperate items. I typed it in, commented out each line, then ran it over and over to see how the error messages would change with the addition of each new line, running first line 1, then 1 + 2, then 1 + 2 + 3, and so on with the results as above. No list of ports. :-( Maybe it's more to do with the machine than processing. I did have a similar setup running on a crappy old XP pentium which gave up the ghost some months ago, and things seemed to work fine then, at least intermittently. This is a brand new beastie, Fujitsu DTL1-02990 running Windows 7, so the OpSys is new as well as the machine. It's got to be a compatibility problem of some sort, especially if the code works for you. Thanks for you assistance, anyway. You are very kind.

Jonny Stu..

Re: Serial library difficulties

1 year ago

Sorry, it's a fine line between assuming missing knowledge and asking insulting questions ;). Are you running the Arduino IDE at the same time? That might be blocking access to the serial port although it's weird that you can't see any serial ports.

pete_w

Re: Serial library difficulties

1 year ago

I've tried it with and without the Arduino IDE running, with the same results. I'll try wiping and re-installing processing, and see what happens. Cheers!

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