Tag Archives: Adafruit Bluefruit

Let your BLE ideas fly with the Adafruit Feather 32U4 Bluefruit

Trust us, Adafruit’s new board is un-BLE-vable! 

Remember when we brought you a first-ever look at Adafruit’s new lineup of Feather boards back at World Maker Faire? Well, as Ladyada herself promised, the new dev boards are thin, light and ready to let your imagination fly! After having already revealed the first two members of the family — the Feather 32U4 Basic Proto and the Feather 32U4 Adalogger — the team shows no sign of slowing down. Next up: the Feather 32u4 Bluefruit.


The Feather 32U4 Bluefruit is said to be their take on an ‘all-in-one’ Arduino-compatible and Bluetooth Low Energy unit with native USB support and battery charging.

“Bluetooth Low Energy is the hottest new low-power, 2.4GHz spectrum wireless protocol. In particular, its the only wireless protocol that you can use with iOS without needing special certification and it’s supported by all modern smartphones,” Adafruit explains. “This makes it excellent for use in portable projects that will make use of an iOS or Android phone or tablet. It also is supported in Mac OS X and Windows 8+.”

Like its other siblings, the Feather 32u4 is built around the mighty ATmega32U4 clocked at 8 MHz and at 3.3V logic. This chip boasts 32K of Flash and 2K of RAM, along with built-in USB so not only does it already integrate a USB-to-Serial program and debug capabilities, it can also act like a mouse, keyboard and MIDI device.


As Adafruit notes, they’ve gone ahed and added a connector for a 3.7V LiPo and a 100mA battery charger. However, the Feather 32U4 will run just fine via microUSB.

“But, if you do have a battery, you can take it on the go, then plug in the USB to recharge,” the team adds. “The Feather will automatically switch over to USB power when its available. We also tied the battery through a divider to an analog pin, so you can measure and monitor the battery voltage to detect when you need a recharge.”

Measuring only 2.0″ x 0.9″ x 0.28” without headers soldered and weighing 5.7 grams, the Feather can be implemented in a wide range of projects. The extremely lightweight and compact board has plenty of pins (20 GPIO), with eight PWM and 10 analog inputs, four mounting holes, a power/enable pin and a reset button. What’s more, the board makes use of the leftover space for a Bluefruit BTLE module as well as two status indicator LEDs.


“The board is capable of much more than just sending strings over the air!  Thanks to an easy to learn AT command set, you have full control over how the device behaves, including the ability to define and manipulate your own GATT Services and Characteristics, or change the way that the device advertises itself for other Bluetooth Low Energy devices to see. You can also use the AT commands  to query the die temperature, check the battery voltage, and more, check the connection RSSI or MAC address, and tons more.”

With Adafruit’s Bluefruit mobile app, you can also quickly prototype your next IoT project using your smartphone or tablet as a controller. This data can be read over BLE and piped into the ATmega32U4.


Among the use cases listed by Adafruit include an HID keyboard, a heart rate monitor and a UriBeacon, to name just a few. The chip comes fully assembled and tested with a USB bootloader that enables you to seamlessly program it with the Arduino IDE.

Intrigued? Fly on over to the Adafruit Feather 32U4 Bluefruit page here. Those wishing to unleash the powers of this impressive board will only have to shell out $30. Not too shabby!

Maker builds a tiny TV with a big remote

Honey, I shrunk the TV set! 

A few years ago, Alec Smecher’s boss brought him a souvenir from Mexico City: a tiny television console made of scrap wood, tinfoil and cardboard. Turns out, this little trinket becomes a perfectly good mini TV when paired with the screen of an old I9000 Android phone that he had lying around.


“Of course, no tiny console is complete without a clunky remote,” Smecher jokes. For this, the Maker chose a large clicker which ironically was larger than the TV itself. There was plenty of room inside the remote for a non-LE Bluefruit module from Adafruit, which could communicate with the I9000.

“The big consideration was how to interface the remote control to the phone. I considered using USB OTG, Wi-Fi, and/or writing some custom software on the phone, but in the end I googled the I9000’s Bluetooth support and found that it was decent, though old, and would happily accept a keyboard or mouse,” Smecher explains.


However, Bluefruit doesn’t support matrix keypads. This led the Maker to implement a barebones ATmega328 that was configured to run its own internal clock source. Since the Adafruit board provides voltage regulation that’s usable by the additional MCU, the remote was able to keep its stock 9V battery power supply.


In terms of software, Smecher says that source code was fairly simple — he employed the Arduino Keypad Library and translated keypresses into mouse and keyboard commands for the Bluefruit using the serial interface. Looking ahead, he notes that he may refine the keys and devise a new template for the remote buttons, but for now it’s good to go. Intrigued? Click on over to the project’s original page or stay tuned to see it in action below!

Capture timelapses with Adafruit’s motorized camera slider

Adafruit upgrades its 3D-printed camera slider with motors and Bluetooth control.

Our friends over at Adafruit love photography, so much so that they recently created a slick slider for their camera. This turned out to be just fine and dandy for hobbyist photographers, but why not take it one step further? Being the Makers that they are, the Ruiz Brothers decided to motorize their existing 3D-printed tool and to add wireless control. Whereas a similar product could run you a couple hundred dollars, this DIY mechanism is fun to build and for a fraction of the cost.


For this iteration, the low-profile slider is motorized using a single NEMA-17 stepper driven by the Adafruit Motor Shield ontop of an Arduino Uno (ATmega328). At its core, the project consists of 500mm slide rail, along with a GT2 timing pulley mounted to a stepper motor, a radial ball bearing and a timing belt that pulls the platform across. As for power, eight AA batteries supply the necessary 12V to the Arduino via a 2.1mm barrel jack.

Though designed with a GoPro or smartphone camera in mind, the slider itself is capable of pushing roughly three to four pounds of weight. This means your point-and-shoot, camcorders and webcams should all suffice, as long as they’re tightly mounted to the unit. The slider should work on any angle and in any position, and doesn’t require a flat surface. This can make for some pretty remarkable timelapses, especially on your iPhone!


“The slider performs the smoothest movement when the timing pulley on the stepper pulls the slider to it,” the Ruiz Brothers write. “Ideally, the platform should be homed when its closest to the radial ball bearing. When the platform slides across in the other direction, the timing pulley pushes the belt, which introduces a slight shake. The shake is noticable in our tests, so we recommend sliding one way.”

Meanwhile, an Adafruit Bluefruit SPI Friend enables you to remotely control the cinematic movement of your camera slider via the Adafruit Bluefruit LE Connect mobile app on any Android or iOS device, including your smartwatch. From the app, you can increase or decrease the speed, start or retract the camera motion, ease in and out, among many other things.


In terms of software, the system uses a controller motor shield Arduino sketch, which features several functions for moving the slider and setting the speed. This sketch calls for both the Adafruit Motor Shield V2 and Adafruit Adafruit BluefruitLE nRF51 libraries.

Intrigued? You can find an exhaustive tutorial of the build here, or simply watch a brief overview below!