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Documentation for Motor Controller with PID Control to use a DC motor as stepper/servo

This code is designed for a motor controller and has merged the PID code of Josh Kopel with the code of the Makerbot servo-controller board. This code can be used on some boards by changing some values.

Hardware Requirements

• motor controller as H-Bridge
• Hall Sensor PCB
• Ramps 1.4 stepper driver

Software Requirements

• PID_v2.h library
• EEPROM.h library

Code Explanation

Motor Driver Type

The type of motor driver is defined using the PWMCONTROL variable. If PWMCONTROL is set to 1, it means that the motor driver has only a PWM interface. In this case, the minimum and maximum values for PWM to turn the motor are defined using PWMMIN and PWMMAX.

Pin Definitions

The pins used in the code are defined as follows:

• encoder0PinA and encoder0PinB: Pins for the Hall Sensor PCB
• MotorIN1 and MotorIN2: Pins for the motor driver (if PWMCONTROL is set to 1)
• MotorDIR and MotorPWM: Pins for the motor driver (if PWMCONTROL is set to 0)
• STEP_PIN and DIR_PIN: Pins for the Ramps 1.4 stepper driver
• EnableLED: Pin for the LED that signals if the MCU is running

PID Values

The default PID values are defined using the MyObject struct. The kp, ki, and kd values are set to 7.00, 0.04, and 0.20 respectively. These values can be changed by the user.

Setup Function

In the setup() function, the following tasks are performed:

• Serial communication is started at a baud rate of 9600.
• The saved PID values are retrieved from the EEPROM. If no values are saved, the default values are used.
• The pins are set to their respective modes.
• Interrupts are attached to the encoder0PinA and STEP_PIN pins.
• The PID is set to automatic mode with a sample time of 2 and an output limit of -255 to 255.

Loop Function

In the loop() function, the following tasks are performed:

• The set