[SOLVED] ATmega32u4 AVR109 bootloader on Mac OSX problems

[jirish]

Hello,

I am new to avr programming, my experience with avr-gcc and avrdude is limited to compiling code and programming attiny13 uCs with the USBtinyISP. I decided to move up to the atmega32u4 to begin work with USB and take advantage of the convenience of a bootloader, however I cannot get the AVR 109 bootloader to work with avrdude.

Here is what happens:

When I plug in the breakout board, my mac recognizes the board as a "network interface". I read other threads concerning this message but found only references to using Teensyduino, which I'm hoping to avoid, as I'm learning to use the avr-gcc toolchain.

I have downloaded the latest version of the Mac CrossPack, however when running the test command in the tutorial

avrdude -p m32u4 -P COM3 -c avr109

I get an error message: avrdude: ser_open(): can't open device "unknown": No such file or directory

Also, a second line appears after a few seconds: Eavrdude: butterfly_recv(): programmer is not responding

Is this bootloader also used on the AVR butterfly? Does this provide a clue as to where I have gone wrong?

I'm not sure what the source of this error is, or why the board is recognized as a network interface. The green LED breathes upon connecting the board, so the bootloader appears to be working.

avrdude version is 2-17-2012

Any help to get me up and running would be great thanks!

-Jon

[adafruit_support_rick]

It's normal for the Mac to show serial devices as network interfaces. It assumes they are modems.
"COM3" is not likely to be the name of a valid Mac serial port. Look in /dev for something along the lines of "tty.usbmodemnnnnnn"
If you've got the Arduino IDE installed, just open it and look in the Tools:SerialPort menu and you should see it.

[jirish]

Thank you driverblock, that was exactly the solution I needed. If this might help anyone else (I'm not sure if the serial port name is specific to my 2011 macbook pro or even my particular unit?), here is the port name that worked for me:

/dev/tty.usbmodemfd121

Once I used the above as the port name in the avrdude command listed in the product tutorial, I was good to go.

Thanks again!

-Jon

[adafruit_support_rick]

I think the Mac starts with /dev/tty.usbmodemfd121, and then has some algorithm for generating a unique ID for subsequent devices. I've got three Arduino UNOs showing up in the Network prefs panel (even though I only have one actual UNO - don't know why it does that). The current name for mine in /dev is tty.usbmodemfd13131

[loopmasta]

Just in case you are still looking for a simple way to find the portname of the conneccted atmega32u4.
I use

Code: Select all

ls /dev/tty.*

and get

Code: Select all

/dev/tty.Bluetooth-Modem /dev/tty.Bluetooth-PDA-Sync /dev/tty.usbmodem142131

where

Code: Select all

/dev/tty.usbmodem142131

is my connected atmega32u4. Then i can use

Code: Select all

avrdude -p m32u4 -P /dev/tty.usbmodem142131 -c avr109

to connect to the AVR.