Arbitary waveform generator using a micro-controller

[Tapajit Mondal]

Hello dear friends,

The following image is that of a Data signal, one waveform is used to represent logic level 1 and other 180 degree phase shifted waveform represents logic 0. Can someone please provide some input on how I may be able to generate the following waveforms on a micro-controller ?

Regards,
TM

 

[MikeMl]

Do you need help with the code, or how to build a two-bit Digital to Analog converter?

 

[Tapajit Mondal]

I need help with the DAC. Since the waveform is a signal, I need sharp edges and fast rise/fall times.

 

[MikeMl]

5V micro?
25mA or 40mA source/sink port pins?
What is the load? (capacitance?)

Here is a guess:

You may have to tweak the resistor values a bit after you see the loaded micro port voltages. PortA can source current to the voltage divider tap; PortB can only sink current.

 

[Ian Rogers]

I do it virtually the same but with only three resistors... But I generate 3.5V 2,2V and 0,7V

4k7 to 5v..
2k4 to one micro pin..
1k2 to the other..

 

[Tapajit Mondal]

Dear Sir,
This image below is the signal on an Oscilloscope. The signal is generated from a Training Setup. Please let me know if any modification is required to the above circuit.