The nonvolatile semiconductor memory device includes a memory cell array
containing a plurality of nonvolatile memory cells and an initial setup
data region in which initial setup data specified to determine operation
conditions of the device is to be written. The device further includes a
detection circuit which detects turn-on of power. The device further
includes a readout circuit which reads out the initial setup data from the
initial setup data region of the memory cell array upon detecting power-on
by the detection circuit. The device further includes a determination
circuit which determines whether the initial setup data read out by the
readout circuit is effective or ineffective. The device further includes a
setup circuit which sets up the device in an operative-prohibiting status
when the initial setup data is determined as ineffective by the
determination circuit.
