A CAMAC data acquisition system for measuring ionization cross section in laser multi-step resonant ionization experiment is described. The number of scalers in the front-end CAMAC can be adjusted by changing the data read-out table files. Both continuous and manual acquisition models are available

and there is a wide adjustable range from 1ms to 800 s with the acquisition time unit. The long-term stability

△t/t

for the data acquisition system with an acquisition time unit of 100 s was measured to be better than ±0.01%

thus validating its reliability in long-term online experimental data acquisition. The time response curves for three electrothermal power-meters were also measured by this DAQ system.