Getting increasing delay in consecutive clock cycles?

[savvej]

In the following code I am trying to send 6 bits of data serially(synchronously) ,with data to be latched on the peripheral on falling edge of clock.
I am using atmega8 with internal oscillator of 1MHz.Using win-avr compiler library and optimization O2 in AVR studio(4.18).

The following is the function:

void Send_Command(unsigned char command)
{
unsigned char i,temp=0;
//setting DATA PIN as OUTPUT
CRTL_PORT_DIR|=(1<<DATA);

for(i=0;i<6;i++)
{

//~~~Changing Data~~~
CRTL_PORT|=(1<<CLOCK);//clock=1
temp=((command>>i) & 0x01);//on DATA(PD0) pin
if(temp)
CRTL_PORT|=(1<<0);
else
CRTL_PORT&=~(1<<0);
_delay_us(1);
CRTL_PORT&=~(1<<CLOCK);//clock=0
_delay_us(1);


}
}


Now when i send "command=0b00000010" ans argument,and simulate the function in Proteus ,I get increasing delay in consecutive clock cycles which is not understandable by me.
I have attached the "Digital Analysis " snapshot with the post. also my c code(which is actually partially complete code to program PIC16f628A).

 

[savvej]

I have attached as said by john blue(on chat saying that maybe using pic may not cause the problem),trying out same code with pic.but heere too they is increasing delay in successive clock cycles.

snapshot & pic project file attached.Code is compiled using PIC C18 compiler and written using MPLAB IDE(8.7).

 

[Ian Rogers]

I ran through this in ISIS the problem here is

        command >> i ;

each iteration is one bigger i = 0 through 5 you should use

        CRTL_PORT|=(1<<CLOCK);//clock=1
	temp &= 0x01;//on DATA(PD0) pin
	if(temp)
		CRTL_PORT|=(1<<0);
	else
		CRTL_PORT&=~(1<<0);
	Delay1TCY();
	CRTL_PORT&=~(1<<CLOCK);//clock=0
	Delay1TCY();
	command >>= 1;

 

[savvej]

Nice one Sir..Good observation...
Thanks....

PS:shouldn't it be "temp=(command & 0x01)" instead of "temp&=0x01" in second line of code you suggested?

 

[Ian Rogers]

Oh yeah sorry, load temp first!! At least you got me thinking. I love a problem