In an experiment with some changes I use this circuit for the development of’m sending you. I could not work because it is not a final time. To put it in principle, be controlled by Pic-5V to +5 V… Electronics Projects, Signal generator Circuit PIC16F88 JAL Code Example “microchip projects, microcontroller projects, pic16f88 projects, 
In an experiment with some changes I use this circuit for the development of’m sending you. I could not work because it is not a final time.
To put it in principle, be controlled by Pic-5V to +5 V analog switch between the output stage is based on the principle of giving. The future with analogue switch (CD4051) 4 units of work for removing a circuit will do better.
Would be best to send with the finished but at the moment I do not have time for this study. The reason for using 16F88 is for adjusting the frequency. Found another pic of the ADC can be used. ADC will connect the potentiometers with a frequency can be adjusted. I try to help to develop friends. Jal the spline drawing software.
Wishing to be useful and good work.
SIGNAL GENERATOR CIRCUIT SCHEMMATIC
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