Serial Port issue on Macbook Pro

Well i have been using an Arduino for the past 6 months on a Windows os. Recently i got a new Macbook Pro and for the past month, the Arduino has been working fine. Yesterday, I plugged it in, and for some reason it wasn't recognized? My computer never has shown its serial port in (Tools) > (Serial Port), but it has been working. I can still draw power from the computer though, so I'm pretty unsure of what's going on... Please help me :slight_smile:

What kind of Arduino? (UNO, duemilinove, MEGA)?
What were you doing before it quit working?
Does it work on your windows computer?

It doesn't work on my windows either, its a duemilanove, and i had just run a script for a servo, but it had worked before....

Do the RX and TX lights happen to be stuck on?

they both flash on and off a few times together. like 8 times then just PWR shows

Does the FTDI chip get warm when plugged in? Does the 3V3 supply pin on the board still work?

it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

theel33:
it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

BAAAAD Idea.

smeezekitty:

theel33:
it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

BAAAAD Idea.

I don't see why is bad idea.
He is just troubleshooting if the USB is actually working and it does.

All what is left to troubleshoot is (maybe) the preferences.

I would delete the preferences (/Users//Library/Arduino/preferences.txt ) while the Arduino program is closed.
This is important, Arduino must be closed. After is closed, you can delete the file. Make a copy if you want to make safer, but Arduino rebuild the file with all the defaults. Nothing will be really lost.

Then run Arduino again and choose your board (that by the way you didn't mention at any time), and choose the serial port ( /dev/tty.usbserial-A800eyms) in case you have the Duemilanove or ( /dev/tty.usbsmodem0000207D1 ) in case you have Arduino Mega ... (or whatever correspond to your board).

Mac is a very friendly environment for Arduino. I've never had problems like Windows or Linux users report.
The only time I had problems is switching to Arduino Mega, and deleting the preferences solved the problem.

Staedtler:

smeezekitty:

theel33:
it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

BAAAAD Idea.

I don't see why is bad idea.
He is just troubleshooting if the USB is actually working and it does.

All what is left to troubleshoot is (maybe) the preferences.

I would delete the preferences (/Users//Library/Arduino/preferences.txt ) while the Arduino program is closed.
This is important, Arduino must be closed. After is closed, you can delete the file. Make a copy if you want to make safer, but Arduino rebuild the file with all the defaults. Nothing will be really lost.

Then run Arduino again and choose your board (that by the way you didn't mention at any time), and choose the serial port ( /dev/tty.usbserial-A800eyms) in case you have the Duemilanove or ( /dev/tty.usbsmodem0000207D1 ) in case you have Arduino Mega ... (or whatever correspond to your board).

Mac is a very friendly environment for Arduino. I've never had problems like Windows or Linux users report.
The only time I had problems is switching to Arduino Mega, and deleting the preferences solved the problem.

Its a bad idea to plug an unresisted LED into the 3.3v output.

smeezekitty:

Staedtler:

smeezekitty:

theel33:
it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

BAAAAD Idea.

I don't see why is bad idea.
He is just troubleshooting if the USB is actually working and it does.

Its a bad idea to plug an unresisted LED into the 3.3v output.

maybe if you leave it ON for 12 hours... It might... but I doubt it too.

Staedtler:

smeezekitty:

Staedtler:

smeezekitty:

theel33:
it doesnt get warm, and i just plugged in an led to that and 5v and it works fine

BAAAAD Idea.

I don't see why is bad idea.
He is just troubleshooting if the USB is actually working and it does.

Its a bad idea to plug an unresisted LED into the 3.3v output.

maybe if you leave it ON for 12 hours... It might... but I doubt it too.

An LED can and will take more then 50ma.
Also this is a useless test as often a fried FTDI chip will still provide power at the 3.3v line, just at different voltage.

Plugging in a LED and seeing if it lights up does not confirm if something is working correctly. First, you really need to be using a current limiting resistor. Not using one shortens the life of the LED and could cause a (otherwise good) power supply to fail.

Second, measuring the voltage is what I was getting at. Does the 3V3 line still ready ~3V? If you attach an LED with resistor (like 300ohm to 1000ohm) does the supply still ready 3V? This troubleshooting step can yield interesting information.

THANK YOU!

If my very recent experience may help...

OK, yesterday I received my Uno board, I connected it to my MacMini and run the Blink test but this failed, I had the RX TX blinking OK but got the error message : avrdude : cannot connect to programmer.
I tried various things, such as power the board with an external PSU but could not get it to work, until I plugged the USB chord directly to the MacMini, until then it was plugged to the USB hub of my Macintosh Display.

Now I plug it directly to the computer and I avoid using the hub. This is not due to a power problem with the hub since it did not operate correctly even when powering the Uno board with an external PSU. This is strange because I use the hub to plug and power an usbpicprog without problems.

yes i used a resistor when testing, of course. but it still hasnt worked and i havent had my computer until today. working on fixing it now.