Highperformance flash version of the 80C51 single-chip 8-bit microcontrollers. It provides 64K Bytes of flash memory including ISP and IAP, 2KB boot flash memory, 2KB EEPROM and 2048 bytes of ERAM. In X2 mode a maximum external clock rate of 20MHz reaches a 300ns cycle time. Primary attention is paid to reducing the device's electro-magnetic emissions.