[SOLVED] Arduino not showing USB port for bootloader hardware.

Other Hardware 3rd Party Boards
1

I bought one Atmega1284 with Omniboot already installed. It works great.

I bought two more Atmega1284 without bootloaders (cheaper), and planned to install the bootloader myself.

First, I tried programming my Arduino Uno to serve as the bootloader. Then concluded that was not working because of software-version differences.

So I bought a hardware bootloader, USBtinyISP, which proved to need drivers, so I downloaded them from AdaFruit, and installed them successfully.

I plugged in the bootloader again and heard the windows chime meaning "successfully started".

Next, I started the Arduino Software and set the Programmer menu to USBtinyISP.

Then I opened the Serial Port menu, only to find my bootloader is not included on the list of ports!

Huhh?

What did I forget to do?

2

I believe avrdude will automatically detect a USBtinyISP, since it sits on the USB bus with a uniquely-identifiable set of USB parameters that can be read. The normal Arduinos need the additional "port" specification because LOTS of things can use the same style of USB/Serial adapter chips, and you're more likely to have more than one arduino connected at the same time.

3

You totally had the answer, westfw. I think I could sum up what you were saying as simply "You don't see a com port number because there ISN'T one. You just plug it in, and it WORKS!"

So I googled "usbtinyisp arduino ide" in search of more info on how to make it just work. That led to this Instuctable which says to "open up arduino ... [and] go to file>upload using programmer".

I did so, and -- lo and behold -- the green LED finally lit up on the little programmer, and my program installed! Naturally, I was anxious to test the newly installed program and yes, it worked perfectly.

I'm still unable to install the bootloader using the hardware programmer. I get the error message "avrdude: verification error, first mismatch at byte ....". Which googling revealed is a bug in the system with solutions beyond what I want to try. And really, I don't need it now anyway. :slight_smile:

There are two obvious advantages to not having an internal bootloader: (1) More memory available for my program, and (2) my program starts instantly instead of waiting to see if the bootloader is going to receive a new program to install.