RESET ADDRESS GENERATING CIRCUIT

摘要

PURPOSE:To deliver a different answer in a manual resetting mode after application of a power supply by securing a setting-enable state for the reset signal when a power supply is applied with operation of a switch provided to a memory and also through a data bus of a microprocessor. CONSTITUTION:When a power supply is applied, a memory address signal of a system start program is set to a flip-flop 10 by an initial reset signal IZ and in the ON/OFF states of a switch 12. While an MPU2 jumps to a reset address and supplies a reset address signal CS and a read signal RD. Thus the memory address signal of the system start program set to a reset address generating circuit 1 by the switch 12 is transferred to the MPU2 via a gate 11 and executed. Then a manual reset signal MRST is produced and the MPU2 jumps again to the reset address. Thus a reset address different from that obtained in an application mode of the power supply is outputted from the circuit 1.