4.0 (Headers)

Teensy 4.0 is a powerful microcontroller board that has gained popularity among hobbyists and professionals for its speed and versatility. It features an ARM Cortex-M7 processor running at 600 MHz, powered by the NXP iMXRT1062 chip, making it one of the fastest microcontrollers available today. It supports Arduino, Micropython, and CircuitPython. This is a "smaller" version, but still has enough RAM to run pretty much any program you could imagine.

I would have preferred the 4.1 but my schedule did not permit waiting longer for it. The product was delivered when promised and is fast enough to emulate other hardware I don’t have. I am comfortable with the Arduino IDE so writing code for this was a simple task. Some of the direct port I/O is not supported the same way it is on the AVR devices. Some of the additional features are not documented very well but there are plenty of examples as with most arduino alternatives as well as a forum to post questions. All in all this is a very capable platform and worked very well for my application. I won’t run into the memory limitations but if you expect to run large programs or save a lot of data locally, order the 4.1.

This guy is fast and will handle everything you throw at it.... For new users, watch out no 5V on any of this guys pins or you'll fry it. Also, I feel it needs a little more experience than an Arduino or similar

Excellent - far better than an ESP32 (though, I do miss the Ethernet feature of the ESP32).First Teensy4.0 project: Thermal Camera...Only 3 stars for 'Value/Money' because the Raspberry-Pi 'PICO' is faster and 1/3rd the price. Nonetheless, I've been an Arduino fan since it's been around and PJRC did an excellent job on the Teensy. Features on Bottom-Side are a bit overkill for a user not interested in them and, Having to Cut copper pad for isolating supply power is NOT user friendly (I stopped doing that after ruining two devices. Thus, I won't attach USB power while using Batteries or Vin)

I've used teensy series for years. This is another great product. Powered from USB, _FAST_, with native floating point instructions. Access to vast array of Arduino libraries. In the Arduino world, most things I try work the first time.

Tiny and fast. If you want micro SD or more pins, please use the version 4.1. The software is a slightly quirky form of Arduino. The speed is simply amazing for it’s size, but the amount of soldering required to add some functionality might be a deal breaker for some. The maximum pin power is pretty low, so expect to need driver circuits for just about everything.

Picked up this and an Octo board to run some addressable LED strips. I was amazed at how easy it was to do. I spent at least 10 times as much time soldering the two boards together as I did setting up the code and testing the LED strips.

Has some quirky behavior not seen in Arduino Nano 33 IOT, but makes up for it in speed and SRAM memory.