May the Fourth with a Special Announcement

It’s been a while since our last news post, but today is May 4, and we pull our heads out of the lab to celebrate our favorite saga and to make an exciting announcement.

Soon you will be able to develop your own props, including lightsabers, on the board we have been developing for the last few months, that is, code name: PropBoard.

It started back in 2013, when we published a small project featuring a DIY sound board for a lightsaber prop. Since then we have received requests from all over the world to recreate and sell such board. As it was basically a bunch of breakout boards and some software hacked together, we couldn’t put it into production. So we have decided to start from scratch and develop an entire new product, that we will anticipate today.

The PropBoard features a Cortex M4 (STM32F401RCT6) running at 84MHz, with DSP instructions and hardware floating point. There are also 3 LED drivers (ST’s LED2001) capable of driving high-power RGB LEDs up to 1.2A on each channel. Audio is generated by reading files from a microSD through 4-bit SDIO clocked at 48Mbps, then mixed in real-time inside the Cortex M4 and digitally sent through I2S to a codec, and output to the speaker with a 2.9W mono Class D amplifier. An NXP MMA8452Q accelerometer will handle the motion sensing. The board supports both 3.7V to 5V power supply range (one 18650 battery for example) and the 5.5V to 12V range (two 18650 batteries).

You may be thinking that handling all that hardware will cost you hours of software development. But we got you covered, because we have developed for you all the software functionality to get your prop running in no-time. Want to play a WAV file? Simply call the play() function and specify the file name. Want to play two or more WAV files that get mixed together? Call play() multiple times. Or set the high-power LEDs brightness with the call of a function, including flickering effects, flash and ramps. All this happening asynchronously, leaving room for your application.

You may still think that you will need to setup a complicated toolchain, that you will need a JTAG and may be to combat with a few makefiles. You will not need any of that, because you will programming the PropBoard right from the Arduino IDE! That’s it, every software function to control the hardware is included and available from the Arduino IDE. All that plus the Arduino goodness you are used to work with: PWM, digital/analog IO, SPI, Wire, etc. The PropBoard comes with a bootloader ready to flash your sketches right from the IDE. A micro USB connector allows you to plug the board to a PC/MAC for download and serial monitor. No need for special drivers since the board includes an FTDI chip to do the serial-to-USB conversion. For the hardcore developer there is of course, the possibility to program the board using the dedicated SWD JTAG connector.

The board was conceived to contain all that hardware in the smallest footprint possible, measuring only 23.90mm x 55.92mm. There is also a row of 2.54mm pins dedicated to general purpose IO, supporting PWM, interrupts, analog channels, SPI, I2C and an extra serial port. On these pins there is plenty of room to connect your hardware, like buttons and extra LEDs.

All the hardware and software will be open-source and available on GitHub. And for an out-of-the-box experience you will be able to download any of the demos we are preparing, with detailed instructions including wiring and setup. We are also in contact with saber and prop builders preparing mechanical parts to fit the board in a professional chassis.

We are already running a pre-production batch and we expect to be shipping this board around June/July. There will be a beta-testing phase and we will be giving some free boards away, so if you have proven experience with Arduino and/or prop building, send me an email to [email protected] or PM on Twitter/Facebook.

Here follows a list of full specs and a very quick video showing some of the thousands of possibilities you will be able to program into the PropBoard. Stay tuned for more news and have fun!

Code name: PropBoard specs

• STM32F401RCT6 Cortex M4 with hardware floating point and DSP instructions, running at 84MHz, with 256KB of flash and 64KB of RAM.
• Digital audio through I2S, capable of playing 24-bit and 16-bit audio up to 96KHz sampling rate.
• On-board Wolfson WM8523 I2S codec with I2C interface and volume/gain control.
• 2.9W Class-D audio amplifier.
• 3 high-power LED output stages with dedicated LED drivers (STmicroelectronics LED2001) with up to 1.2A of source current, with thermal shutdown and LED disconnection protection. The current is simply controlled with PWM.
• microSD slot with push-push system.
• 4-bit SDIO access clocked at 48MHz supporting FAT16 and FAT32 filesystems (optionally exFAT).
• NXP MMA8452Q 3-axis digital accelerometer with dedicated interrupt pins.
• On board 5V and 3.3V LDO.
• Power supply range: 3.7V to 5V and 5.5V to 12V. The board can be converted to one range or the other by the means of solder jumpers.
• 15 GPIO pins featuring PWM, serial port, I2C, SPI, interrupts and analog channels.
• SWD JTAG pins.
• On-board FTDI serial-to-USB converter.
• Micro USB connector.
• API with libraries to play WAV files, mix sounds, drive the high-power LEDs, manage the motion sensor and power down modes, buttons and more.
• Programmable from the Arduino IDE by just downloading a board package.
• 3 mounting holes.
• 4 layers PCB with ENIG contacts.