Stepper Motor Control: Schematic

The Schematic
           First thing I'll do is warn you, this circuit is not fun to look at nor is it fun to implement, it takes a bit of effort. Since there are two coils in our stepper motor we'll use two LMD18245's to control the current flow through the coils.
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           It is important to note that there are motor control chips like the L298 that offer stepper motor control using only 1 chip. You can also find chips that have the capability of controlling two of these 2 coil stepper motors at once, the SN754410 for example.

Here is an example of what your completed circuit should look like:

           Next we'll see take a look at the code necessary to control the stepper motor and see exactly why control of the current flow direction is so important. Scroll down to the bottom to download the source code file.