The LeafLabs Maple is a microcontroller board based on the STM32F103RB microprocessor. The Maple runs at a maximum of 72 MHz, has 39 digital input/output pins, 16 analog inputs, native full speed USB, 3 USARTs (hardware serial ports), integrated SPI/I2C support, a power jack, and a reset button. Maple is programmable over USB via our provided DFU bootloader, no extra hardware required! Users can also program the onboard program flash via external JTAG interface. Maple offers security support for read/write protected addresses, as well as User and Handler processor modes. It has a real-time sysTick, useful for a real time OS or any timing senstitive applications. Four built-in 16-bit timers will help you here as well. Maple can be powered via USB, a wall adapter, or it can run off of a rechargeable LiPo battery (see below for more info).

For those of us who love and are familiar with Arduino, Maple is offered in an Arduino-compatible format, complete with Arduino pin layouts and programming environment.

Note: the photo, schematic and board layout displayed are for Maple revision 5.