This program controls an x-y plotter. Can be used to draw basic lines and shapes

tiny_plotter.c

 
#include <xc.h>
#include <libpic30.h>
#include <stdio.h>
#include <math.h>
#include<uart.h>


 
// Configuration settings
_FOSC(CSW_FSCM_OFF & FRC_PLL16); // Fosc=16x7.5MHz, i.e. 30 MIPS
_FWDT(WDT_OFF);                  // Watchdog timer off
_FBORPOR(MCLR_DIS);              // Disable reset pin

//Functions
void setup(void);
void x_step_pos(int n);
void x_step_neg(int n);
void y_step_pos(int n);
void y_step_neg(int n);
void sine_draw(void);
void x_y_plot(int x, int y);
void square_example(void);
void pen_up(void);
void pen_down(void);
void draw_circle(int r);



//Variables
int count = 0;

int t = 0;
int xpoint;
int ypoint;
int n;
int x_state = 1;
int y_state = 1;
int _EEDATA(2) table[] = {2,3};
int x,y;





int main(void)
{
	setup();
	int temp = 0;
	
	while(1) 
	{
		void draw_circle(100);
	}

		
		
	while(1);
}

void setup(void)
{
	//configure pins
	TRISD = 0b00000000;
	TRISC = 0b00000000;
	TRISF = 0b00000000;
	
	//pwm setup
	PWMCON1 = 0x00FF;     // Enable all PWM pairs in complementary mode
    PTCONbits.PTCKPS = 3; // prescale=1:64 (0=1:1, 1=1:4, 2=1:16, 3=1:64)
    PTPER = 9375;         // 20ms PWM period (15-bit period value)
    PDC1 = 1406;          // 1.5ms pulse width on PWM channel 1
    PTCONbits.PTEN = 1;   // Enable PWM time base
	
	U1BRG = 48;            // 38400 baud @ 30 MIPS
	U1MODEbits.UARTEN = 1; // Enable UART
	
	
}

void x_step_pos(int n)
{
	count = 0;
	while( count < n )
	{
		if (count == n) break;
		if (x_state == 4)
		{
			_LATD1 = 1;
			__delay32(300000);
			_LATD1 = 0;
			count++;
			x_state =3;
		}
	
	
		if (count == n) break;
		if (x_state == 3)
		{
			_LATD3 = 1;
			__delay32(300000);
			_LATD3 = 0;
			count++;
			x_state = 2;
		}
	
	
		if (count == n) break;
		if (x_state == 2)
		{
			_LATC13 = 1;
			__delay32(300000);
			_LATC13 = 0;
			count++;
			x_state = 1;
		}
	
		if (count == n) break;
		if (x_state == 1)
		{
			_LATC14 = 1;
			__delay32(300000);
			count++;
			_LATC14 = 0;
			x_state = 4;
		}
	}
	xpoint = xpoint + n;
	
	
}

void x_step_neg(int n)
{
	count = 0;
	while( count < n )
	{
		if (count == n) break;
		
		if(x_state ==1)
		{
			_LATC14 = 1;
			__delay32(300000);
			_LATC14 = 0;
			count++;
			x_state = 2;
			
		}

		if (count == n) break;
		
		if (x_state == 2)
		{
			x_state = 3;
			_LATC13 = 1;
			__delay32(300000);
			_LATC13 = 0;
			count++;
			x_state = 3;
			
		}	
		
		if (count == n) break;
		
		if (x_state ==3)
		{
			_LATD3 = 1;
			__delay32(300000);
			_LATD3 = 0;
			count++;
			x_state = 4;
		}
		if (count == n) break;
		
		if (x_state == 4)
		{
			_LATD1 = 1;
			__delay32(300000);
			count++;
			_LATD1 = 0;
			x_state = 1;
			
		}
	}
	xpoint = xpoint - n;

}

void y_step_pos(int n)
{
	count = 0;
	while(count < n)
	{
		
		if (count == n) break;
		if( y_state == 1)
		{
			_LATD0 = 1;
			__delay32(300000);
			_LATD0 = 0;
			count ++;
			y_state = 2;
		}
		if (count == n) break;
		if (y_state ==2)
		{
			_LATF5 = 1;
			__delay32(300000);
			_LATF5 = 0;
			count++;
			y_state = 3;
		}
		if (count == n) break;
		if (y_state == 3)
		{
			_LATD2 = 1;
			__delay32(300000);
			_LATD2 = 0;
			count++;
			y_state = 4;
		}
		if (count == n) break;
		if (y_state == 4)
		{
		_LATF4 = 1;
		__delay32(300000);
		count++;
		_LATF4 = 0;
		y_state = 1;
		}
	}
	ypoint = ypoint + n;
	
		
}

void y_step_neg(int n)
{
	count = 0;
	while(count < n)
	{
		if (count == n) break;
		if (y_state == 4)
		{
			_LATF4 = 1;
			__delay32(300000);
			_LATF4 = 0;
			count++;
			y_state = 3;
		}
		
		if (count == n) break;
		if (y_state == 3)
		{
			_LATD2 = 1;
			__delay32(300000);
			_LATD2 = 0;
			count++;
			y_state = 2;
		}
		
	
		if (count == n) break;
		if (y_state == 2 )
		{
			_LATF5 = 1;
			__delay32(300000);
			_LATF5 = 0;
			count++;
			y_state = 1;
		}
		if (count == n) break;
		if (y_state == 1)
		{
			_LATD0 = 1;
			__delay32(300000);
			count++;
			_LATD0 = 0;
			y_state = 4;
		}
	}	
	ypoint = ypoint - n;
	
}

void sine_draw(void)
{
	
	while(1)
	{	
		int v = 0 ;
		int f = 1;
		int n = 0;
		t = 0;
		while( t < 200 )
		{
			v = 200*sin(2*3.14*f*t);
			v = abs(v);
		//	printf("%d\n",v);
			x_y_plot(t,v);
			t++;
			
		}
		x_y_plot(0,0);
		t = 0;
		
	}
	
	
}

void x_y_plot(int x, int y)
{
	int x_steps = 0;
	int y_steps = 0;
	
	x_steps = x - xpoint ;
	y_steps = y - ypoint;
	//printf("x_step = %d    y_step = %d x_point = %d y_point = %d\n",x_steps, y_steps, xpoint, ypoint);
	
	if (x_steps > 0)
	{
		x_steps = abs(x_steps);
		x_step_pos(x_steps);
	}
	if (x_steps < 0)
	{
		x_steps = abs(x_steps);
		x_step_neg(x_steps);
	}
	
	
	if (y_steps > 0)
	{
		y_steps = abs(y_steps);
		y_step_pos(y_steps);
	}
	if (y_steps < 0)
	{
		y_steps = abs(y_steps);
		y_step_neg(y_steps);
	}
	
}

void square_example(void)
{
	while(1)
	{
		if((x<200) && (y<200))
		{
			x = x+20;
			y = y+20;
			x_y_plot(x,y);
			x_y_plot(0,0);
		}
		else if ( x>200 || y>200)
		{
			x_y_plot(0,0);
			break;
		}
	}
}

void pen_up(void)
{
	 PDC1 = 700; 
	 __delay32(15000000);
}

void pen_down(void)
{
	PDC1 = 1500;
	__delay32(15000000);
}

void draw_circle(int r)
{
	pen_up();
	
	x_y_plot(100,100);
	
	
	int theta = 0;
	while(theta <= 360)
		{
			
			y = 100 +(r*sin(theta *(3.14/180))) ;
			x = 100+(r*cos(theta *(3.14/180))) ;
			printf(" x = %d,   y = %d, theta = %d\n",x,y, theta);
			x_y_plot(x,y);
			if (theta == 0) pen_down();
			
			theta++;
		}
	pen_up();
	x_y_plot(0,0);
}