Arduino Other Boards Technology
The New Teensy 4.0: Big Brains, Tiny Body

The latest itty bitty powerhouse from PJRC has been released this week. The teensy line of dev boards has hit 4.0! They have managed to keep a tiny footprint, like you’ve come to expect from the Teensy. They’ve gained some serious horsepower thanks to the ARM Cortex-M7 running running at 600Mhz. Check out these CoreMark scores compared to the previous versions.


Here is a tidy list of all the specs for the board, available now from the PJRC store for $19.95

  • ARM Cortex-M7 at 600 MHz
  • 1024K RAM (512K is tightly coupled)
  • 2048K Flash (64K reserved for recovery & EEPROM emulation)
  • 2 USB ports, both 480 MBit/sec
  • 3 CAN Bus (1 with CAN FD)
  • 2 I2S Digital Audio
  • 1 S/PDIF Digital Audio
  • 1 SDIO (4 bit) native SD
  • 3 SPI, all with 16 word FIFO
  • 3 I2C, all with 4 byte FIFO
  • 7 Serial, all with 4 byte FIFO
  • 32 general purpose DMA channels
  • 31 PWM pins
  • 40 digital pins, all interrrupt capable
  • 14 analog pins, 2 ADCs on chip
  • Cryptographic Acceleration
  • Random Number Generator
  • RTC for date/time
  • Programmable FlexIO
  • Pixel Processing Pipeline
  • Peripheral cross triggering
  • Power On/Off management

I personally have used Teensy for a few years because it was one of the first boards I had easy access to that would do full USB HID emulation, meaning that if I programmed it as a keyboard or mouse, any computer would see it as one without installing additional drivers. That was very useful for the devices I was building at the time, though admittedly I never really needed a ton of processing power.

Paul from PJRC supplied a list of some uses that would take advantage of the new brains:

Polyphonic audio synthesis using the Teensy Audio Library can require considerable processing power, especially with many modulated waveforms and complex effects.  Teensy 4.0 will allow these synth projects to use more advanced synthesis models for more simultaneous voices.

Only fairly simple machine learning models can run on today’s mainstream microcontrollers.  While powerful models will still require single board computers or dedicated hardware, Teensy 4.0 will open up the possibility to run moderately complex models in real time in the small low-power Teensy form factor, for tasks like gesture recognition.

Real time audio analysis, whether using machine learning or traditional techniques like Fourier Transform and correlation & convolution, will also greatly benefit from Teensy 4.0’s performance, which can be easily embedded into costumes or props.

High-res color TFT graphical displays often tax today’s microcontrollers. In addition a fast CPU and larger memory for rendering, Teensy 4.0 includes a pixel pipeline for hardware assisted alpha blending, color space transform, and other graphical operations.  You can add a TFT display and build a user interface with little impact to other real-time using Teensy 4.0.

Fast data acquisition often requires moving or storing large amounts of data in real time, only to have a PC perform filtering as an initial
processing step.  With Teensy 4.0 performance, initial processing can become feasible in real time.


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