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Update msr3-controlling-dc-motor.md with correct duty range #1821

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Update msr3-controlling-dc-motor.md with correct duty range #1821

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Update msr3-controlling-dc-motor.md with correct duty range 
The tutorial describes the accepted range of values for indicating the work duty of the motors as 0-100. In testing, it is determined that the actual range of values is 0-255. A value of 100 is actually less than half of the maximum allowed work duty.
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@kerbinite
kerbinite authored Mar 18, 2024
commit 2c5c5572187092ec1b1c8840fbc0033156ebae37
4 changes: 2 additions & 2 deletions ...or-shield-rev3/tutorials/msr3-controlling-dc-motor/msr3-controlling-dc-motor.md
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Expand Up @@ -44,7 +44,7 @@ There are several ways we can control a DC motor, perhaps the easiest one is jus

But if we want to do a bit more than just making a motor spin full speed in two directions, we need a **motor control circuit.** More specifically, the dual full-bridge driver [L298P](https://www.st.com/resource/en/datasheet/l298.pdf), which we can find on the Motor Shield Rev3.

With this IC, we can set the work duty (0-100), enable brakes (HIGH, or LOW), and set the direction (HIGH or LOW). Each of these features can be controlled using a different set of pins. As we are going to control a DC motor in this tutorial, let's take a look at the pins that are used:
With this IC, we can set the work duty (0-255), enable brakes (HIGH, or LOW), and set the direction (HIGH or LOW). Each of these features can be controlled using a different set of pins. As we are going to control a DC motor in this tutorial, let's take a look at the pins that are used:

Channel A:
- **D12** - Direction
Expand Down Expand Up @@ -83,7 +83,7 @@ First, let's take a look at some key commands in the code. We are actually not u
- `int brakePin = 9;` - assign brake pin.
- `digitalWrite(directionPin, state)` - sets the direction of the pin by using HIGH or LOW states.
- `digitalWrite(brakePin, state)` - release or activate brakes, using HIGH or LOW states.
- `analogWrite(pwmPin, 30)` - write a value between 0-100 to set the work duty.
- `analogWrite(pwmPin, 30)` - write a value between 0-255 to set the work duty.
- `directionState = !directionState` - a boolean that switches every time the loop is run.

The sketch can be found in the snippet below. Upload the sketch to the board.
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