Microprocessor having self-programmed eprom

Abstract

A single-chip microcomputer comprises a CPU (1), a RAM (2), an EPROM (3), a timer (4), serial I/O communication logic (5), four I/O ports (11-14) and an input pin for providing a RESET signal or programming potential V.sub.PP (23). An EPROM control register (53) in the CPU is loadable under the control of a computer program stored in an external memory (40). Responsive to a first bit in the EPROM control register an address buffer/latch 61 and a data latch 62 temporarily latch address and data information during a write operation to the EPROM. Responsive to a second bit in the EPROM control register the programming potential is applied to the EPROM for a predetermined time to program the data information into the EPROM at its associated address. The accuracy of the programming operation may be verified using the CPU under the control of the external computer program, to compare the address and data information programmed into the EPROM with the original source of such information.

Dependencies are inferred from the claim text.