Dumbot Code

This is the operating code for a robot I built called Dumbot.  It only has a motion sensor and moves randomly.  The code generates three random numbers: speed, time, movement type.  There are five different movement types: Forward, backward, turn right, turn left, and stop.  There is a check routine at the  beginning: Forward, right, backward, left.  To check to make sure the motors are installed properly.  This code was tested on a PIC16F1825, using hobby motors from Sparkfun and the brushed motor controller breakout board from Sparkfun.  A switched battery holder with three double A batteries from Jameco was used.  The wheels and frame were 3D printed.  An LED output and an audio output were included.

In order to make sound I use a 386 audio amplifier and a PCB mounted speaker.  I wanted the robot sound to be coming from the robot operations themselves, and I wanted it to be a bit like R2D2 so I send the PWM from the motors to the output.  The one trick I added was to increase the frequency of the pulses when the motor goes faster, so the speaker makes a higher pitched sound when it runs faster.

/* 

 * File:   R06Main.c

 * Author: hmikelson

 *

 * Created on September 4, 2018, 6:11 PM

 */

#include <xc.h>

#include <stdio.h>

#include <stdlib.h>

#pragma config MCLRE=OFF,CP=OFF,WDTE=OFF,FOSC=INTOSC

#define _XTAL_FREQ 16000000

unsigned char sPORTA, sPORTC, pwmax=31;

void init()

{

    //Configure GPIO Port

    TRISA = 0b110000000;  //Set all Output

    TRISC = 0b110001000; //Set up pin 3 for input

    OSCCONbits.IRCF = 0b1111;

    OSCCONbits.SCS = 0b00;

    //OPTION_REG = 0b01111111; //Global enable weak pullups

    //WPUC = 0b00001000;     //Enable weak pullups with a 1

    // Set up analog input

    ANSELCbits.ANSC3 = 1;

    ADCON0 = 0b00011101; //Channel (CHS4:0 bits 6-2),ADON bit 1 enable Analog

    ADCON1bits.ADCS = 0b111; // clock select dedicated osc 

    ADCON1bits.ADNREF = 0; //neg ref

    ADCON1bits.ADPREF = 0; //config + voltage with vdd

    ADCON1bits.ADFM = 1; //format left justified

    ADRESH = 0x00;        //Init the AD Register

    ADRESL = 0x00;       // I don't think this is needed

    //OSCCONbits.SPLLEN = 0b1;

}

void vdelay(int n)

{

    int i;

    for (i=0;i<=n;i++)

    {

     __delay_us(100);

    }

}

int read_v()

// Read voltage from input

 {

    int val,v1,v2;

    __delay_ms(1);

    ADCON0bits.GO_nDONE = 1;

    while(ADCON0bits.GO_nDONE == 1);

    v1 = ADRESH;

    v2 = ADRESL;

    val = (v1<<8) + v2;

    return val;

 }

// Drive robot forward

void RobotFd(int time, unsigned char speed)

{

    int i, j;

    for (i=0;i<time;i++)

    {

        for (j=0;j<pwmax;j++)

        {

            if (j<speed)

            {

                PORTA = 0b00111110;  // 

                PORTC = 0b00010110;  // Enable on pin 4

                vdelay(pwmax/speed);

            }

            else

            {

                PORTA = 0b00000110; // I think there is a  clock output on pin 4 which I don't know how to disable

                PORTC = 0b00010010; // Enable on pin 4

                vdelay(pwmax/speed);

            }

            

        }

        

    }

}

// Drive Robot backward

void RobotBk(int time, unsigned char speed)

{

    int i, j;

    for (i=0;i<time;i++)

    {

        for (j=0;j<pwmax;j++)

        {

            if (j<speed)

            {

                PORTA = 0b00111101;

                PORTC = 0b00010101;

                vdelay(pwmax/speed);

            }

            else

            {

                PORTA = 0b00000101;

                PORTC = 0b00010001;

                vdelay(pwmax/speed);

            }

            

        }

        

    }

}

void RobotRt(int time, unsigned char speed)

{

    int i, j;

    for (i=0;i<time;i++)

    {

        for (j=0;j<pwmax;j++)

        {

            if (j<speed)

            {

                PORTA = 0b00111110;

                PORTC = 0b00010101;

                vdelay(pwmax/speed);

            }

            else

            {

                PORTA = 0b00000110;

                PORTC = 0b00001001;

                vdelay(pwmax/speed);

            }

            

        }

        

    }

}

void RobotLt(int time, unsigned char speed)

{

    int i, j;

    for (i=0;i<time;i++)

    {

        for (j=0;j<pwmax;j++)

        {

            if (j<speed)

            {

                PORTA = 0b00111101;

                PORTC = 0b00110110;

                vdelay(pwmax/speed);

            }

            else

            {

                PORTA = 0b00000101;

                PORTC = 0b00001010;

                vdelay(pwmax/speed);

            }

            

        }

        

    }

}

void RobotSt(int time)

{

    int i;

    for (i=0;i<time;i++)

    {

    PORTA = 0b00000100;

    PORTC = 0b00001100;

    __delay_ms(10);

    }

}

void main()

 {

  int rmode, rtime, volts,mt=31;

  unsigned char rspeed, nactions=0;

  init();

  RobotFd(100,pwmax/2);

  RobotSt(1);

  RobotRt(100,pwmax/2);

  RobotSt(1);

  RobotBk(100,pwmax/2);

  RobotSt(1);

  RobotLt(100,pwmax/2);

  RobotSt(1);

  while(1)

   {

     if (nactions > 0)

     {

         rmode=(rand() & 7) + 1;

         nactions=nactions-1;

     }

     else

     {

         rmode = 0;

     }

     rtime = (rand() & 7)+1;

     rspeed = rand() & pwmax;

     switch (rmode)

      {

       case 1:

        RobotFd(rtime*mt,rspeed);

        RobotSt(1);

        break;

       case 2:

        RobotBk(rtime*mt,rspeed);

        RobotSt(1);

        break;

       case 3:

        RobotRt(rtime*mt,rspeed);

        RobotSt(1);

        break;

       case 4:

        RobotLt(rtime*mt,rspeed);

        RobotSt(1);

       break;

       case 0:

        RobotSt(1);

        volts = read_v();

        if (volts>50)

         {

            nactions = 10;

            //blink(volts);

         }           

       break;

       default:

           RobotSt(10);

        break;

      }

   }

 }