Microchip Technology, Inc. AT89C5131A-M

High-performance flash version of the 80C51 single-chip 8-bit microcontroller with full-speed USB functions. This device retains the features of the Microchip 80C52 and adds 1024 bytes of on-chip expanded ERAM, dual data pointer, 16-bit up/down timer, programmable counter array, up to four programmable LED current sources, programmable hardware watchdog, and power-on reset. Two software-selectable modes of reduced activity further reduce power consumption. In the idle mode the CPU is frozen while the timers, serial ports, and interrupt system operate. In the power-down mode the RAM is saved and the peripheral clock is frozen, but the device has full wake-up capability through USB events or external interrupts.