As Various ATM equipments have been worldwidely developed to realize ATM networks for accommodating diverse services with a wide range of traffic characteristics, various testings of these equipments are required to check whether they meet the required qualities. In this study, we implement an ATM traffic generator by utilizing a proposed traffic generation mechanism which can generate various kinds of single source traffic models as well as multiplexed ATM traffic streams. Using Texas Instrument's TMS320C40 DSP chip as a main processor, we can generate various ATM source traffic streams including CBR, POISSON, ON-OFF, IPP, and MMPP models and multiplexed streams of CBR, POISSON, ON-OFF, and IPP models. We show that the experimental results agree very well with the analytical ones. The result of this study can be utilized in testing various ATM equipments including broadband network terminations and ATM switches.