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If you’re looking for the BUB 1 it’s here
If you’re looking for the BUB 2 it’s here

USB to TTL serial adapter

The BUB III is here!

It’s blue, in honor of the Jee Internationale.

It’s tiny (2cm x 1.6cm x .7cm). (the smallest FTDI option besides an FTDI cable)

It’s flexible (can be reflashed so the LEDs indicate whatever you want).

Feature list:

  • Red and green LEDs show serial activity on both the TX and RX lines.
  • Jumper pads to select between 5 to 3.3 volt power level
  • Jumper pads to select between 5 and 3.3 volt logic level
  • A capacitor on the DTR line to facilitate interfacing breadboard & DIY Arduinos.

The output header is arranged with the same signals as the FTDI RS232 cable (and the same as the same as the BBB/RBBB/LilyPad/Arduino Pro etc, etc) pin header, with the added bonus of having the DTR line instead of having to use the RTS line (with its attendant quirks. The official Arduino schematics also use DTR signal instead of the RTS.

No second socket like the classic BUB. We have a feeling some dedicated hackers will still want BUB “classic”, so it’s still available. No power options, like the BUB II– also still available.

Default Options

The BUB III ships with the 5V power option soldered by default and the 3.3V logic level option soldered by default. This will result with power (VCC) at 5 volts and signal logical levels at  3.3 volts. This works on Optiboot and Decimilia bootloaders on every Freeduino / Arduino board we’ve tested.

Package Contents

The BUB III ships alone, the 1×6 female header soldered to the bottom.
The BUB III uses the micro USB header, same as most Android phones.
We have it available as an option in the dropdown menu with a 1′USB A to micro-B cable. These are common cables, and used with most modern Android phones- so you probably have one laying around.

Other length cables are available on our USB cables page.

The I/O jumper sets the logic level on the signal pins, 3.3v by default:

The VCC jumper sets the voltage on the VCC pin, 5v by default:

Installing FTDI Drivers

The BUB III, like all boards that use an FTDI chip for a USB communications link, needs drivers installed.
Download the appropriate drivers for your operating system from this page.

Follow the standard procedures for installing drivers.
On a Mac, just click on the dmg file and install. On Windows, follow the links after the “Found new hardware” message appears.
You may need to visit the device manager for confirmation or to reinstall.

Modern GNU/Linux kernels have FTDI drivers installed by default. Easiest option if you don’t is to upgrade your kernel.

Once the FTDI drivers are installed, you should see the virtual serial port show up in Arduino -> Tools -> Serial Ports, if you’re using the Arduino IDE. It should appear / disappear when you plug / unplug the BUB.


FTDI VCP (virtual com port) drivers page
About the FT231X on FTDI’s website
Eagle schematics and board design at Github
Schematic in pdf format
FTX-prog to reflash firmware (optional; all BUBs come pre-flashed)

Additional information

Weight 45 g
Dimensions 2 × 1.6 × .1 in

BUB only, with 1' USB cable

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