The first Arduino was serial, and over the decade and a half, this has been the default way to upload code to an Arduino board. In 2008, support for in-circuit programmers was added, and later port detection was added. The latest version of the Arduino IDE adds something new: pluggable discovery. Now any protocol is supported by the Arduino IDE.

This feature is the brainchild of [Paul Stoffregen], creator of the Teensy. If you’ve ever used a Teensy, you’ll remember the Teensyduino application used to upload code to the board. The Teensy uses HID protocol instead of serial for uploading. After working to improve the integration between the Teensy and Arduino IDE, [Paul] stated extending the DiscoveryManager. After some discussion with the Arduino developers, this feature was then added to Arduino 1.8.9, released a month or so ago.

There are some issues with Pluggable Discovery, most importantly that it doesn’t yet exist in the Arduino Command Line Interface (yeah, that exists too). If you’re looking to contribute to Open Source, that would be a nice project to pick up.

With the right JSON, and configuration, it is now theoretically possible to extend the Arduino IDE to any sort of protocol. This means (again, theoretically), it’s possible to update the firmware in your DIY MIDI synth over SysEx message, or a parallel port, maybe. Someone is going to upload to an Arduino board over PCIe, eventually.

[Paul Stoffregen], known as father of the Teensy, has leveraged the Teensy 3.1’s hardware to obtain some serious speed gains with SPI driven TFT LCDs. Low cost serial TFT LCDs have become commonplace these days. Many of us have used Adafruit’s TFT LCD library  to drive these displays on an Arduino. The Adafruit library gives us a simple API to work with these LCDs, and saves us from having to learn the intricacies of various driver chips.

[Paul] has turbocharged the library by using hardware available on Teensy 3.1’s 32 Freescale Kinetis K20 microcontroller. The first bump is raw speed. The Arduino’s ATmega328 can drive the SPI bus at 8MHz, while the Teensy’s Kinetis can ramp things up to 24MHz.

Speed isn’t everything though. [Paul] also used the Freescale’s 4 level FIFO to buffer transfers. By using a “Write first, then block until the FIFO isn’t full” algorithm, [Paul] ensured that new data always gets to the LCD as fast as possible.

Another huge bump was SPI chip select. The Kinetis can drive up to 5 SPI chip select pins from hardware. The ATmega328 doesn’t support chip selects. so they must be implemented with GPIO pins, which takes even more time.

The final result is rather impressive. Click past the break to see the ATmega based Arduno race against the Kinetis K20 powered Teensy 3.1.

Paul’s library is open source and available on Github.