Hello guys, my first post here. I'm making a project where I need some range of values from some sensor to control a Pure data values, I tried using the Serial.Write function from Arduino and sending it to an Analog Input, but the PWM from Arduino is not really precise and reliable. I bought an "Arduino Due" which has 3 RX/TX ports, I was hoping serial communication would make it, but I can't find the way. I would really appreciate some help. Thanks in advance.
How do I make Bela receive serial communication from arduino within pure data?
- Edited
memorg1120 Serial.Write function from Arduino and sending it to an Analog Input
hmmm how is that supposed to work?
memorg1120 , but the PWM from Arduino is not really precise and reliable.
You'd need at least a lowpass filter for an Arduino's PWM output to be readable from an analog input.
I spent an afternoon getting some serial in into Pd to work. You'll need to:
- update your board to the latest
dev
branch (see here) - also have a Pd file similar to this in your project (source here)
Feedback welcome .... I guess it's hard to provide a universal way of parsing the serial input, so it would be nice for either allowing format specifiers (e.g.: ffssff
to parse a space-separated input into a list of float-float-symbol-symbol-float-float). Another useful feature could be to pass the input to Pd as "binary", i.e.: as a list of floats between 0 and 255, each representing one byte. This is equivalent to netsend/netreceive -b
feature, but it's mostly unclear to me what that is supposed to be used for unless you have a dedicated external that can parse that back into useful stuff (e.g.: oscparse/oscformat).
- Edited
Hey man, thanks for the great answer, I can see all the hard work you did.
giuliomoro hmmm how is that supposed to work?
Sorry, I meant analogWrite.
giuliomoro I followed your steps, but i don't think that i succeeded. Arduino is running the example 'AnalogInOutSerial' at 115200 rate I connected it to the USB in of the BeagleBone and build your pd example with the render.cpp, but it doesn't print anything. I'm getting a successful build with this error : Error from tcgetattr: Input/output error. Any pieces of advice?
Did you change /dev/ttyS4 in the patch for the path of the usb serial device you are using?
giuliomoro how can i find it? im a bit confused of how can i access bela's terminal without ssh.
Just type ls /dev/tty{USB,ACM}*
in the console at the bottom of the IDE. That should display most USB connected UART devices
PS: if you want to connect to the board via SSH instead, use ssh root@bela.local
Hello! I stumbled upon this thread because I try to do something similar. I got it to run the way you described with the above pd sketch and render.cpp. I am sending a series of floats as text, separated by space and ending with a newline character. It works somehow but also it seems there are numbers getting lost on the way. I am sending ten numbers (changed the unpack and pack accordingly) but I get sometimes 5, sometimes 7, sometimes ten and also they seem to get mixed up. I tried to reduce the frequency in which the Arduino sends but even at once per second it happens. Any ideas why? Thanks in advance!
I also tried to send the numbers as bytes (I mapped it to 0-255 so one byte per number because it doesn't really matter whether I get the actual values for me) and changed "newline" to "none" but then I got only zeroes ...
I have made some improvements to the SERIAL features in the past months and I just pushed a simpler but better documented example (PureData/serial). So make sure you get the latest dev
branch of Bela on your board and that you remove any .cpp file from your Pd project, then try again and come back if you still have trouble.
Among the new features, you can now set bytes
as the type and receive individual bytes as a value between 0 and 255.
Thank you very much! I tried and it seems to work now.
- Edited
giuliomoro Hi! I'm trying to make sense of Serial reading into PureData, and I can find " a simpler but better documented example (PureData/serial)". I've got the lastest dev branch of Bela on my board. Any advise?
I'm trying to send data from arduino to PureData running on Bela, i'm running the PD patch that is shared upper, and printing the values. Even though they look good on Arduino Serial Monitor, In Bela its strange, I'm not receiving every values, and it's changing variables order. I was trying to look for the example that you wrote about.
Sorry if this is a simple question that i'm not getting, and thank you!
This is the example: https://github.com/BelaPlatform/Bela/tree/dev/examples/PureData/serial
If it's not on your board, then it's likely that you are not actually running the latest dev
branch. From the IDE go to settings -> other system functions -> version info and report what you see there.
- Edited
giuliomoro , hmmm i'm still trying to make sense of "running the latest dev branch". I know i've updated Bela recently.
Ok, just got to the instructions on hwo to update to experimental release, and i'm updating to the dev branch right now!
This is was what i got on my version info:
This is after updating to dev branch:
And there is it! Thank you!
Unfortunately i'm getting inconsistent readings more than 5 variables.. Until 5 variables, i get the values print on Bela console right. With 6 variables values start jumping in a strange way.
On the Arduino:
Serial.print(gY, 0);
Serial.print(" ");
Serial.print(gZ, 0);
Serial.print(" ");
Serial.print(val_bme_temp, 0);
Serial.print(" ");
Serial.print(val_bme_alti, 0);
Serial.print(" ");
Serial.print(val_bme_humi, 0);
Serial.print(" ");
Serial.println(val_peso, 0);
Thank you again ;_;
Hey, I cant send more that 4 variable values, any suggestion? Thank you!
sergio_coutinho With 6 variables values start jumping in a strange way.
Can you say more about this? I am wondering if what's happening is that the data is received and passed to Pd just fine and the issue is only with the printing
giuliomoro hey,
Arduino:
Serial.print(aX, 0);
Serial.print(" ");
Serial.print(aY, 2);
Serial.print(" ");
Serial.print(aZ, 2);
Serial.print(" ");
Serial.print(aSqrt, 2);
Serial.print(" ");
Serial.print(gX, 0);
Serial.print(" ");
Serial.print(gY, 0);
Serial.print(" ");
Serial.print(gZ, 0);
Serial.print(" ");
Serial.print(val_bme_temp, 0);
Serial.print(" ");
Serial.print(val_bme_press, 0);
Serial.print(" ");
Serial.print(val_bme_alti, 0);
Serial.print(" ");
Serial.print(val_bme_humi, 0);
Serial.print(" ");
Serial.print(val_peso, 0);
Serial.print("\n");
delay(200);
and in Bela PureData, i've tried multiple prints, but the ones that should work:
Inconsistent readings, at least printing:
nothing shows on the last unpacked float, and the first ones are inconsistent (like the console printed values)
Thank you for your help again!
ok there was a bug in the code handling that. Try creating a new render.cpp file in your Pd project and paste the content of this one into it, then rebuild the project and try again: https://raw.githubusercontent.com/BelaPlatform/Bela/dev/core/default_libpd_render.cpp
giuliomoro It works! Thank you!
With this render file i have no problem in unpack all variables coming from serial!