An imaging apparatus with a timing generator supplying an imaging device with drive pulses. The timing generator has registers for independently storing information required for generating a pulse pattern for the imaging device. A selector selects one of the registers to connect it to a pulse generator. Based on the information stored in the selected register, the pulse generator generates pulses of a pulse pattern for the imaging device. External control circuitry rewrites the information stored in an unselected register from the outside of the timing generator. By repeating the steps of selecting one of the registers and rewriting the information stored in the unselected register, drive pulses with various pulse patterns can be supplied to the imaging device.