All the power of a 32-bit ARM Cortex-M4 development board that offers a whole heap more oomph for your micro-controller based project while being as easy to program as an Arduino. Now with an improved 3.3V regulator, to allow Teensy to directly power ESP8266 Wifi, WIZ820io (W5200) Ethernet, and other power-hungry 3.3V devices. Ideal for tasks that need more power or memory than most AVRs can offer such as driving displays, digital signal processing, and complex calculations. Teensy has a whopping 64K of RAM (32 times more than an Arduino Uno!) and 256KB of flash storage. Teensy uses 3V3 logic (though is tolerant of 5V) so makes an ideal match for projects also involving a Raspberry Pi since there is no need for level conversion. Powered and programmed over USB Programmable using Arduino software (with the Teensyduino add-on) 72MHz ARM Cortex-M4 processor (overclockable to 96MHz) 256KB flash storage 64KB RAM 16 DMA channels 34 IOs including: 21 x 16-bit analogue inputs 12 x PWM outputs 1 x 12-bit DAC output 2 x I2C bus 1 x SPI 3 x UART 12 x Touch sense inputs Most programs written for Arduino work on Teensy. All of the standard Arduino functions (digitalWrite, pinMode, analogRead, etc) all work on Teensy. Teensyduino is also compatible with many Arduino libraries. Much, much more detail can be found at the official Teensy website. Full Teensy 3.2 schematic can be found here
