Design and implementation of an embedded network arbitrary signal generator

In this paper we use an embedded system and an external interface circuit to design and implement an embedded network arbitrary signal generator (ENASG). We build a Web server in the embedded system and use CGI (common gateway interface) as the network interface between the Web server and the embedded system. The user can use a PC, a PDA or a smart phone to login to the remote operation interface. After the user has selected and adjusted the output waveform, it is outputted through the external interface circuit. For the ENASG we design four waveform types: sine, square, triangle and arbitrary. The frequency and the voltage of the output waveform are adjustable. The external interface circuit includes the data buffer, the digital-to-analog converter (DAC), the oscillator and the amplifier. The data buffer receives and stores the output waveform data from the embedded system. The oscillator controls the DAC to load the output waveform data and to convert the data into an analog signal. Finally, the amplifier gains the analog signal which is then outputted.