Embedded Digital Control with Microcontrollers

5Conversion Between Analog and Digital Forms

This book is on digital control. However, actual control signals are in analog form most of the times. These should be represented in digital form so that they can be processed by the STM32 microcontroller. As the digital signal is processed or desired control signal is generated by the microcontroller, it should be converted to analog form. Hence, it can be applied to the analog system to be controlled. For both cases, we need methods for converting analog and digital signals from one to other. There are solid mathematical theories explaining how these conversions can be done. We will start with explaining them in this chapter. Besides theory, one needs practical methods to convert analog and digital signals. Modern microcontrollers (as candidate digital control system platforms) have dedicated hardware for this purpose. We introduced such hardware on the STM32 microcontroller in Chapter 2. We will focus on how this hardware can be used both in Python and C languages in this chapter. Hence, the reader will be able to process an analog signal on the microcontroller and feed the processed signal to outside world in analog form.

The user may have an analog controller working as desired which has been designed beforehand. We may want to represent it in digital form as code. Hence, we can duplicate the existing analog controller in digital form such that no analog parts are needed for its implementation. This way, we can benefit from ...