Microchip AT89LP51RD2-20JU, 8bit 8051 Microcontroller, AT89LP, 20MHz, 64 kB Flash, 44-Pin PLCC

Single-cycle microcontroller with 64KB ISP flash and 12-clock compatibility mode. It includes 2304 bytes RAM, 2KB ROM with UART-base Bootloader, PWM, UART, TWI, SPI, PCA, up to 42 I/Os, 10-bit A/D, dual Analog Comparators, an internal 8MHz RC oscillator, and on-chip debug. The TWI and On-Chip Debug features are not available on 40-pin PDIP package.