FastWrite

help please,

does 1 have idea why following code outputs jittery signal?  attached scope image.

thanks!!

code: [select]

int pinone = 9;
int pintwo = 10;


#define fastwrite(_pin_, _state_) ( _pin_ < 8 ? (_state_ ?  portd |= 1 << _pin_ : portd &= ~(1 << _pin_ )) : (_state_ ?  portb |= 1 << (_pin_ -8) : portb &= ~(1 << (_pin_ -8)  )))
// macro sets or clears appropriate bit in port d if pin less 8 or port b if between 8 , 13

void setup() {
 
   pinmode(pinone, output);   // set outpin pin output
   pinmode(pintwo, output);
 
}

void loop()
{
 
 fastwrite(pinone, high);       // set pin high
 //delaymicroseconds(20);    // waits "on" microseconds
 fastwrite(pintwo, high);
 delaymicroseconds(20);
 fastwrite(pinone, low);        // set pin low
 //delaymicroseconds(20);   //wait "off" microseconds
 fastwrite(pintwo, low);
 delaymicroseconds(20);
 
}

main() has call loop() , there interrupts going on in background micros()/millis() time tracking.

try this:

code: [select]


void loop(){
while (1)
{
 fastwrite(pinone, high);       // set pin high
 //delaymicroseconds(20);    // waits "on" microseconds
fastwrite(pintwo, high);
 delaymicroseconds(20);
 fastwrite(pinone, low);        // set pin low
//delaymicroseconds(20);   //wait "off" microseconds
fastwrite(pintwo, low);
 delaymicroseconds(20);

}
}
[color=#222222]


will main() , loop() jitteryness anyway.

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