The EF6805U3 Microcomputer Unit (MCU) is a member of the 6805 Family of low-cost single-chip Microcomputers. The 8-bit microcomputer contains a CPU, on-chip CLOCK, ROM, RAM, I/O, and TIMER. It is designed for the user who needs an economical microcomputer with the proven capabilities of the 6800-based instruction set. A comparison of the key features of several members of the 6805 Family of Microcomputers is shown at the end of this data sheet. The following are some of the hardware and software highlights of the EF6805U3 MCU.