Patent ID: 7420606

Claim:
A timing generator comprising: a first memory circuit that stores timing generation information; a first register for holding the timing generation information in the first memory circuit; a second register that holds control function information as the timing generator; a first external input part for accessing the first register so as to rewrite data therein; a selector that selects one of the first memory circuit and the first external input part in order to conduct writing of data in the first register; and a second external input part that supplies the selector with a selection signal; a pulse generation part that generates a pulse timing in accordance with the timing generation information held in the first register and the control function information held in the second register so as to output a single or a plurality of pulses; an input control part that selects either the first register or the second register in which data input from the first external input part is to be written, wherein the selector selects data to be input in the first register from an output of the first memory circuit and an input out of the input control part in accordance with the selection signal supplied from the second external input part, and during a time period when the data input from the first external input part is written into the first register, the pulse generation part is initialized; and wherein during a time period when data is written in the first register, an output of the pulse generation part is fixed at any one of a high, a low and a high impedance state and after completion of the writing of the data in the first register, a pulse is output in accordance with the timing generation information held in the first register.