The DS89C4x0 single-cycle 8051 processors come with flash memories up to 64 kbytes. They can be programmed by an application. The devices also include two full-duplex UARTs, 13 interrupt sources with five priority levels, and variable length MOVX timing. Dual pointer instruction enhancements allow data transfers in excess of 2 Mbytes/s. Prices for the processors start at $7.