I tried this without success. Here is my code to make a simple oscilloscope. I tried using the Graph but found it to be slow and had difficulty to make it reset reliably. Also it is less universal.
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The PIC is a PIC16F1459 used in the Rapid USB Prototyping Stick. This is a cool tool to develop a USB application. It is not as capable as using an ICD but remarkably suitable for the purpose.
Thanks for the suggestion to poll the IRQ Bit. I will try this. If I use the PWM I will have more hardware to get a complementary output that I can turn off when I read the echo from the ultrasonic. ...
I am trying to drive an ultrasonic transducer at around +/-40khz. It may be necessary to tune the transducer to resonance. The project is based on a Rapid USB proto stick since it matches my target go ...