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Update StepperModes.md

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A typical stepper motor has two sets of coils, *A* and *B*. Applying a current to one or both coils creates a magnetic field that fixes the motor's position. Any changes to the direction and/or magnitude of the current flowing through the coils causes the motor to "step" to a new fixed position. By repeatedly changing the current flow according to a specific pattern the motor can be made to continuously step clockwise or counterclockwise. The specific pattern chosen, known as the *step mode* in the **StepperControl** class, determines the size of the step and overall performance of the motor. The speed at which changes to the current flow are made determines the speed at which the motor rotates. The modes supported by **StepperControl** are described below. A typical stepper motor has two sets of coils, *A* and *B*. Applying a current to one or both coils creates a magnetic field that fixes the motor's position. Any changes to the direction and/or magnitude of the current flowing through the coils causes the motor to "step" to a new fixed position. By repeatedly changing the current flow according to a specific pattern the motor can be made to continuously step clockwise or counterclockwise. The specific pattern chosen, known as the *step mode* in the **StepperControl** class, determines the size of the step and overall performance of the motor. The speed at which changes to the current flow are made determines the speed at which the motor rotates. The modes supported by **StepperControl** are described below.
### FULL STEP TWO PHASE ### FULL STEP TWO PHASE (withouth PWM)
In this mode, a constant current is applied to both coils *A* and *B*. The motor is stepped by alternatively flipping the direction of the current flow in each coil as follows: In this mode, a constant current is applied to both coils *A* and *B*. The motor is stepped by alternatively flipping the direction of the current flow in each coil as follows:
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Since in this mode each coil has only two possible states (i.e. the direction of the current flow), only one digital signal per coil is required to implement the stepping pattern. However, fully flipping the direction of the current flow in a coil changes the magnetic fields very rapidly, which creates a rather clunky motion when stepping the motor. Since in this mode each coil has only two possible states (i.e. the direction of the current flow), only one digital signal per coil is required to implement the stepping pattern. However, fully flipping the direction of the current flow in a coil changes the magnetic fields very rapidly, which creates a rather clunky motion when stepping the motor.
### FULL STEP ONE PHASE ### FULL STEP ONE PHASE (without PWM)
In this mode, a constant current is applied to only one coil, either *A* or *B*, at the same time. The motor is stepped by alternatively applying the current to each coil, while also flipping its direction as follows: In this mode, a constant current is alternatively applied to either *A* or *B*, while also flipping its direction as follows:
<img width="250" alt="image" src="https://github.com/HomeSpan/HomeSpan/assets/68477936/cbf2fea5-072e-4fef-9231-504bb483b0c0"><br> <img width="250" alt="image" src="https://github.com/HomeSpan/HomeSpan/assets/68477936/cbf2fea5-072e-4fef-9231-504bb483b0c0"><br>
This mode uses only half the power as the FULL STEP TWO PHASE mode since current only flows through one coil at a time. Also, though the step size is the same, the transtition from one step to another is not as harsh since the direction of the current is never flipped while flowing. However, since in this mode each coil has three possible states for current flow (positive, negative, and off), two digital signals per coil are required to implement the stepping pattern. This mode uses only half the power as the FULL STEP TWO PHASE mode since current only flows through one coil at a time. Also, though the step size is the same, the transtition from one step to another is not as harsh since the current to each coil transtions from one direction to zero before flipping to the other direction. However, since in this mode each coil has three possible states for current flow (positive, negative, and off), two digital signals per coil are required to implement the stepping pattern.
### HALF STEP ### HALF STEP (without PWM)
Though the the step sizes for the two modes above are the same, the
<img width="434" alt="image" src="https://github.com/HomeSpan/HomeSpan/assets/68477936/ec317c77-fbd9-4641-9d50-d822b477c9ec"><br> <img width="434" alt="image" src="https://github.com/HomeSpan/HomeSpan/assets/68477936/ec317c77-fbd9-4641-9d50-d822b477c9ec"><br>