RESET CIRCUIT FOR MICROCOMPUTER DEVICE

PURPOSE:To easily constitute a circuit which recognizes power-on reset for power-on and reset due to the other factors to perform the reset processing corresponding to each factor. CONSTITUTION:A CPU 3 having the non-maskable interrupt function (NMI function) is used, and the processing is performed in accordance with software held in a memory 5 as follows; flag data is read in from a specific flag area in the memory 5 simultaneously with input of a CPU reset command signal from a register 4 and is compared with a specific value indicating the other reset factors, and this specific value is written in the flag area and the power-on reset processing is performed in the case of disaccord as the result of comparison, but the reset processing due to the other factors is performed otherwise, and contents of the flag area are forcibly set to flag data for power-on by the NMI function if a power source 1 outputs an abnormality signal PF/L.