Electronic – arduino – Can’t get upload code to Arduino UNO from Ubuntu 12.04

To be able to bootload code on the Arduino, the programmer must attempt to connect within about 3 seconds of the AVR coming out of reset. I the ArduinoBT I have lacks a connection that the traditional USB versions have, which allows the programming software to reset the Arduino by itself. In lieu of that, you must physically hit the button to do it yourself.

I cannot see how can I press the reset button on the Arduino during the upload when I have to type the PIN in a different window.

You should only have to type the Bluetooth passkey once, so after the BT module is paired with your computer, the computer should be able to freely connect, so long as it is powered.

The Bluetooth module and AVR are very separate; you can hold the AVR in reset, and the Bluetooth module will happily run along. If you're cutting power to the entire board to reset it, it may indeed be difficult to have the BT module come online, connect to it, and initiate programming all within 3 seconds.

That error usually means that AVRdude missed the window to send something before the bootloader dropped through to the already loaded sketch.

Some arduino bootloaders have a different wait-for-program delay (or none at all) depending on the reset source (poweron, reset pin, or watchdog).

Do you have a schematic (didn't find one on DFR site)? Are you applying reset the same way each time, or differently the first time (power on vs reset-from-serial-DTR maybe?)