Seeeduino Lotus Cortex-M0+ is a SAM D21 Microcontroller development board. The Atmel® | SMART™ SAM D21 is a series of low-power microcontrollers using the 32-bit ARM® Cortex®-M0+ processor with 256KB Flash and 32KB of SRAM. you can consider the Seeeduino Lotus Cortex-M0+ as a combination of Seeeduino and Base Shield. Seeeduino Lotus Cortex-M0+ has 14 digital input/outputs (10 of which support PWM) and 6 analog input/outputs, 3 Serial Communication Interface, a micro USB connector, a JST2.0 Li-Po connector, an ICSP header, 12 Grove connectors, a reset button. Seeeduino Lotus Cortex-M0+ is an upgraded version of Seeeduino Lotus V1.1, it replaces a more powerful chip, optimizes the circuit layout, and the power supply is more stable. Because this chip supports direct USB level output, there is no need to use a serial port to USB chip, like CP2102N. Therefore, one more hardware serial port is available to the user. Features Compatible with Arduino UNO ARM® Cortex®-M0+ 32bit 48MHz microcontroller(SAMD21) 12 on-board Grove connectors 14 Digital I/O Pins (10 PWM outputs) 6 Analog Inputs Support Power Path Management Support micro-usb or Li-Po battery powered 2A maximum charging current Suitable for low power design Attention All the I/O pins are 3.3V, please do not input more than 3.3V, otherwise the CPU may be damaged.The output voltage range of the VSYS pin is 3.5v-4.6v，Please don't use the VSYS pin to power board more than 4.6v. Hardware Overview Pinout