AVR Programming interface Outline

Ive drawn up a little outline of what how i think my interface will work.

I know how to read binary from serial, read pots via ADC, and output PWM. I have a winch motor on order and 2 professionally etched Tronic H-Bridges.. So hopefully I can start to put things together.

can those microcontroller gurus out there tell me if im on the right path with my outline?

I havent included alot in there, for example the POT will be much higher resolution that the 8bit PWM channels I will have, so I will need conversations etc..

I found the Atmel PID.c PID.h source files.. ive implemented them to a little test proggie:

I find it takes a lot more cycles than I think it should to settle at the correct value

Code:

#include <avr/io.h> 
#include <stdio.h>
#include <stdlib.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include pid.h
#include lcd.h
#include <string.h>

#define NO_OF_POTS 3
#define potSensitivity 10

//To Do. make these values editable via lcd and buttons
double K_P = 3;
double K_I = 5;
double K_D = 3;


struct PID_DATA pidData1;





void Init(void)
{
	//Setup PID structs
	pid_Init(K_P, K_I, K_D, &pidData1);
  
  
	/* Init LCD */
	lcd_init(LCD_DISP_ON);
	
	lcd_clrscr();
	lcd_puts(Init Okay);
	
	
   
}

int DoPid(int16_t desiredValue, int16_t acualValue, struct PID_DATA *pidData)
{
	return pid_Controller(desiredValue, acualValue, pidData);
}

int main(void)
{
	Init();
	int desiredPosition = 500;
	int actualPosition = 200;
		
	while (1)
	{
	
	
	
		
		if (1)
		{		
			char potString[7];						
			char LCDline2[17];
			
			
			int PWMvalue = DoPid(desiredPosition, actualPosition, &pidData1);
			
			
			itoa(actualPosition, potString, 10);						
			
			itoa(PWMvalue, LCDline2, 10);
			
			lcd_clrscr();					
			lcd_puts(potString);
			lcd_gotoxy(0,1);
			lcd_puts(LCDline2);

			actualPosition += PWMvalue;
			_delay_ms(100);
			
			
		}
		
		
		
		
	}
}