AVR-Chat

Hi,

I'm having this weird problem whereby I am able to debug, and to step 
through the program, but it just ignores/skips some of the lines.

In the code below, I'll show the skipped lines with \\<<< at the end.

Any ideas, please?

Thanks,

Cat


#include <inttypes.h>
#include <avr/io.h>
#include <stdio.h>



volatile uint8_t iMotorPosition[9] = {0, 0b110110, 0b100110, 0b110101, 
0b010101, 0b111001, 0b101001, 0b111010, 0b011010};
volatile uint8_t iOldInput = 0;
uint8_t iBitsChanged = 0;	//moved here because AVRstudio gives "Location not 
valid" when inside "ReadInput"
int8_t iStepX = 1;			//The steps will become negative when direction changes
int8_t iStepY = 1;				//or I'll set them according to the actual HI/LO value
int8_t iStepZ = 1;
int8_t iCurrentStepX = 1;
int8_t iCurrentStepY = 1;
int8_t iCurrentStepZ = 1;


void SetupPorts (void);
void ReadInput(void);


int main (void)
{
	SetupPorts();                    \\<<<
	while(1)
	{
		ReadInput();
	}
}

void ReadInput(void)
{
	uint8_t iNewInput = PIND & 63;	//<<<Read port D and mask (keep) only the 
lower 6 bits \\<<<
	if (iNewInput == iOldInput)
		return;
//Set Step signs
	iStepX = bit_is_set(iNewInput, 0) ? 1 : -1;
	iStepY = bit_is_set(iNewInput, 2) ? 1 : -1;
	iStepZ = bit_is_set(iNewInput, 4) ? 1 : -1;

//Find out which bits changed and act accordingly
	iBitsChanged = iNewInput ^ iOldInput;				//We use "^" (XOR) to check which 
bits have changed
	iOldInput = iNewInput;								//Save New input as Old for next time

//Mask direction bits in iBitsChanged MAYBE NOT NEEDED
	iBitsChanged &= 0b101010;

	if (bit_is_set(iBitsChanged, 1))		//If X-step changed
	{
		if (bit_is_set(iNewInput, 1))		//And if it changed to HI
		{
			iCurrentStepX +=iStepX;
			if (iCurrentStepX == 9)
				iCurrentStepX = 1;
			if (iCurrentStepX == 0)
				iCurrentStepX = 8;
			PORTA = iMotorPosition[iCurrentStepX];
		}
	}

	if (bit_is_set(iBitsChanged, 3))		//If Y-step changed
	{
		if (bit_is_set(iNewInput, 3))		//And if it changed to HI
		{
			iCurrentStepY +=iStepY;
			if (iCurrentStepY == 9)
				iCurrentStepY = 1;
			if (iCurrentStepY == 0)
				iCurrentStepY = 8;
			PORTB = iMotorPosition[iCurrentStepY];
		}
	}

	if (bit_is_set(iBitsChanged, 5))		//If Z-step changed
	{
		if (bit_is_set(iNewInput, 5))		//And if it changed to HI
		{
			iCurrentStepZ +=iStepZ;
			if (iCurrentStepZ == 9)
				iCurrentStepZ = 1;
			if (iCurrentStepZ == 0)
				iCurrentStepZ = 8;
			PORTC = iMotorPosition[iCurrentStepZ];
		}
	}
}

void SetupPorts(void)
{
	DDRD = 0;				//PortD ->Input
	DDRA = 0xFF;			//PortA ->Output X
	DDRB = 0xFF;			//PortB ->Output Y
	DDRC = 0xFF;			//PortC ->Output Z

}