PURPOSE: To obtain a timing and waveform generator where timing can be changed or pulse can be stopped by modifying memory description for waveform control information.

CONSTITUTION: A timing and waveform generator is provided with a pattern generator 10, a frequency generator 20 that generates a frequency Ta having a relation of a=n×Tb based on a pattern information generating from the generator 10, a frequency generator 30 that generates Tb. Further, it is also provided with a waveform control part 50 that generates a waveform equivalent to the memory content to be accessed through the Ta and pattern information, a delay generator 70, a counter 40 where the Ta is used as a reset signal and the Tb as a clock signal respectively, a waveform control part 60 that generates a waveform equivalent to the memory content to be accessed through a pattern information and a frequency Tb generating in the counter 40, and a delay generator 80.