Chip characteristics The dual-core Cortex M0+ has a main frequency as high as 133MHz; 2. External Quad-SPl flash memory with internal execution (XIP) 3. High-performance full crossover bus architecture; 4. On-board USB 1.1 (Device or host) 5. 12-bit 500 KSPS analog-to-digital Converter (ADC) 6. Dual programmable I0 (PIO) peripherals; 7.264K multi-bank high-performance SRAM 8.30 multi-functional universal input/output ports (GPIO): 2x UART, 2X I2C, 2X SPI, 4xADC, 1 A timer with 4 alarms and 1 real-time clock;