Re: LPT square wave


rpodraza@xxxxxxxxx wrote:
Hi,

I'm trying to write a program in C++ to communicate with an AVR
microcontroller's SPI via the LPT port.

I have to generate a clock (SCK) signal on one of the pins of the LPT.
I am using the WinIO library. I'd like to have way to create a square
wave of a given frequency (within some limit of course).

My question is: what is the best way to generate such signal and what
is the maximum frequency one can obtain? Excluding of course such code:
Code:

for (;;) {
pin = 0; pin = 1;
}


What's wrong with:

for(;;){
pin = 0;
wait_a_very_precise_amount_of_time();
pin = 1;
wait_a_very_precise_amount_of_time();
}

.

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