Mini DDS (Direct Digital Synthesis)
This is a very simple version of the Direct Digital Synthesis, using just the AT90S2313 and a resistor network.It’s controlled over RS232 from a small Windows program, and can generate Sine, Sawtooth, Trangle and Sqare waves ranging from 0.07 Hz to about 200-300 kHz in 0.07 Hz steps (depending on your crystal).
   Mini DDS (Direct Digital Synthesis)
Read more on Mini DDS (Direct Digital Synthesis) website
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