The high-performance, low-power 8/16-bit AVR XMEGA microcontroller combines 256KB in-system programmable flash memory (8KB boot code section) with read-while-write capabilities, 4KB EEPROM, 16KB SRAM, a four-channel event system, a programmable multi-level interrupt controller, 50 general purpose I/O lines, a 16-bit real time counter, five flexible 16-bit timer/counters with capture, compare and PWM channels, USB Full-speed Device, three USARTs, two two-wire interfaces, two serial peripheral interfaces, one 16-channel/12-bit ADC with programmable gain, two analog comparators with window mode, a programmable watchdog timer with separate internal oscillator, accurate internal oscillators with PLL and prescaler, and a programmable brown-out detection.