Processing 2.0b7 Serial.bufferUntil() not working?

Core Library Questions

grovesr

Processing 2.0b7 Serial.bufferUntil() not working?

in Core Library Questions • 8 months ago

Hi,
I am experimenting with serial communication between Processing and an AVR microcontroller (ATMEGA328). I am on Windows XP and have successfully used Processing 1.5 and 1.5.1 to send and receive serial data to/from the microcontroller.

Now I have downloaded the 32 bit Processing 2.0b7 code. I specifically wanted the 2.0 Processing code because I am interested in exporting my application via the command line (actually from a Tcl script), and command line export is not available until version 2.0 and later.

On 2.0b7, I do the exact same thing as I was doing in 1.5.1and the bufferUntil() never triggers a serialEvent. To track it down, I went with the simplest example script from Tom Igoe as detailed here http://processing.org/reference/libraries/serial/Serial.html. The program never seems to receive the line feed from the microcontroller. I do see evidence of the serial link sending the data because I have a USB-Serial converter with a RX/TX LED and I see it flash.

Again, I ran the exact same code in Processing 1.5.1, and it works fine.

Does anyone have any suggestions for getting this to work in 2.0b7?

Thanks for any ideas.

Rob

Replies(3)

akseidel

Re: Processing 2.0b7 Serial.bufferUntil() not working?

8 months ago

I am having no problems with 2.0b7 using .bufferUntil('\n') and I am developing back and forth between OS X and Windows 7 machines. The problem could be that the until signal ("\n" for my case) is not being sent. You might need to create a diagnostic that does not use the bufferUntil that reveals exactly what is coming in so you can determine exactly what is going on. Remember that the computer is very most likely doing exactly what you are telling it to do. So if bufferUntil() never triggers serialEvent then bufferUntil() never actually buffers until. The until marker must not be coming in.

grovesr

Re: Processing 2.0b7 Serial.bufferUntil() not working?

8 months ago

Hi akseidel,
Thanks for the response.

I would agree with you, but I run the exact same code on Processing version 1.5.1 and it runs fine. From this I infer that the '\n' is in fact being sent from my microcontroller. In fact, there is a lot of handshaking communication taking place on the serial connection between Processing and the microcontroller that is all working perfectly on version 1.5.1, and not at all on 2.0b7. You say you have been developing in OS X and Win 7, I don't suppose you have tried with a Win XP machine?

Has anyone else successfully used Serial.bufferUntil() on a Win XP machine in version 2.0b7? Or any 2.0+ version?

akseidel

Re: Processing 2.0b7 Serial.bufferUntil() not working?

8 months ago

You are right. I have not tried my current project on Win XP. I think my previous project did not look for \n. I think I was using a scheme that bracketed all of the data from the Arduino with some character. In the current project the stuff from the Adrunio is explicitly starting with \n as in Serial.print("\nMessage") Serial.print("rest of message"). It naturally happened that way because the Ardrunio side was built first using the serial monitor to debug the Arduino side of the scheme before starting the Processing side.

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