Design and implementation a control interface by touch panel for an embedded arbitrary waveform generator

In this paper we use an embedded system to design and implement an arbitrary waveform generator. Its modules are a touch panel and the DAC interfaces. The user draws arbitrary design waveforms on the touch panel. The embedded system then draws a straight line between two points using the Bresenham line algorithm which is like a piecewise linear method. After recording the information of the waveform, the embedded arbitrary waveform generator outputs the signal when the user touches ldquoRunrdquo. In addition, the embedded arbitrary waveform generator also provides the basic waveform output, adjustment frequency and voltage. The basic waveform includes sine, triangle and square waveforms. The DAC interface that we have designed includes data buffer, DAC and crystal and amplifier. The embedded system sends the data of the waveform to the data buffer when the user touches ldquoRunrdquo, then sends the control signal to read the digital data and to the DAC conversion. Currently this design outputs for one channel. We can extend that to more than two channels if we increase the DAC interface of the same structure. Then our design can adjust the frequency of the crystal and the capacity of the data buffer to raise the output frequency. Raising the frequency of the crystal raises the output frequency. Raising the capacity of the data buffer provides a wider range of output frequency.