mac app output gibberish - no signal

[sabdolla]

Hi, I just got an Arduino Uno and the pulse sensor. I downloaded the mac app too and followed all instructions. For some reason, the "serial monitor read-out" output of the pulse sensor mac app does not show anything, just some gibberish letters when I try 1) "static boolean serialVisual = true;", or 2) "static boolean serialVisual = false;".

[yurygitman]

Gibberish letters means the serial communication is working. It's mostly likely a speed setting on serial.

Can you upload second screen shot of gibberish when you change the serialVisual "true/false" setting on Arduino.

[sabdolla]

Sure, this is "true": and this is "false": They seem the same to me, but not sure maybe something I don't know. Looking forward to hearing back. Thanks, Sara

[yurygitman]

If you open Arduino monitor in Arduino what do you see, with true and false changed and uploaded to Board ?

Serial Monitor in Arduino is Opened/Closed with the "magnifying glass icon" in the control panel.

Please post shot-screen grab of Arduino's Serial Monitor. What should be the last clue here.

Also is the "purple cable" in the AO (Analog 0) pin on Arduino?

[yurygitman]

Also, when you open the Mac App, did you "refresh ports" and select the "..tty.USB..." Option?

From your screen shot it looks like a serial port maybe not actually be selected. Double check that selection.

[sabdolla]

Hi, I think I know where the problem might be: the port. Opening the Arduino monitor, I get the following message "Board at COM1 is not available". The Arduino website says that for a Mac, the following ports should be available: However, my Macbook Air only has these limited ports: I tried to go on different websites and blogs to see if someone has this port problem, and some people do, but I haven't tried a proposed solution that works. What most suggest is installing the FTDI driver, however, Arduino Uno boards apparently don't have an FTDI hardware to need this driver. Any suggestions?

Thanks,

[yurygitman]

You have the right Port. In your screen cap of Arduino select Tools/Port/dev/cu.usbmodem1411 (Arduino Uno).

That should work for you. I believe info online is confusing you b/c it is for boards before the Uno...?

1) Please select above Port. 2) Open File>Examples>Basics>Blink

3) Upload that to your board with Upload Icon. You can see if everything works correctly with this Blink example.

4) Try to change the Blink code from:

void loop() {
  digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);              // wait for a second
  digitalWrite(13, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);              // wait for a second
}

To:

void loop() {
  digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(100);              // wait for a second
  digitalWrite(13, LOW);    // turn the LED off by making the voltage LOW
  delay(100);              // wait for a second
}

and you should see the Pin 13's LED blink at a different speed.

5) OK, if all this work, your Arduino and Computer are talking correctly. Hooray! You can then upload the Pulse Sensor Code.

[sabdolla]

Wow! Thank you so much, it worked.

I now have a question about the output, the serial monitor read-out window continuously outputs things (e.g. s502, s503, etc.), even when my finger is not in the pulse.

Should I only pay attention to the top bar that ranges from 50 to 140? Are the units BMP?

Also, I am wondering if I can run the visualization code for mac or is it specific to windows?

Thank you so much, Sara

[yurygitman]

Sara, I'm going to close this issue's item, OK. The "Serial Gibberish" item is settled....

Please repost your second question with the GitHub Issues tab of the software in question. Screen-grabs & snapshots of your Arduino/PulseSensor are worth a thousand words. :+1:

Let's address other questions like that.... Thanks!