Threads

kostas
Offline
Premium Member

07 Oct 2011 10:22 #13738 by kostas

Replied by kostas on topic Re:Threads

Maybe you could use a oneshot component before the enable pin, for generating the one clock pulse needed?

Please Log in or Create an account to join the conversation.

fma
Offline
Senior Member

07 Oct 2011 10:31 #13739 by fma

Replied by fma on topic Re:Threads

The problem is to generate the trigger signal...

Please Log in or Create an account to join the conversation.

fma
Offline
Senior Member

07 Oct 2011 10:57 #13741 by fma

Replied by fma on topic Re:Threads

Ok, I found: siggen!

Question: in the oneshot comp, does width=0 mean the minimum duration of the out signal?

Please Log in or Create an account to join the conversation.

andypugh
Offline
Moderator

07 Oct 2011 13:29 #13751 by andypugh

Replied by andypugh on topic Re:Threads

Yes, 0 = one thread invocation.

I am surprised that sampler doesn't feature a divider parameter. I think that somebody should add one.

Please Log in or Create an account to join the conversation.

fma
Offline
Senior Member

07 Oct 2011 17:24 #13764 by fma

Replied by fma on topic Re:Threads

I'll have a look at that comp, and see if I can add this feature...

Please Log in or Create an account to join the conversation.

fma
Offline
Senior Member

14 Oct 2011 07:12 #13906 by fma

Replied by fma on topic Re:Threads

I finally wrote a clock comp, which has both normal 50% duty cycle output pin and pulse output pin. The pulse pin remains TRUE only for 1 thread cycle. Connecting this pulse output to the sampler.enable pin does the job.

Here is the code; feel free to comment it:

component clock "Generate a clock signal";

pin in bit enable=TRUE "enable clock";
pin out bit out=FALSE "50% duty cycle clock output";
pin out bit pulse=FALSE "pulse clock output";
param rw unsigned freq=1000 "clock frequency";

function _ nofp;

// Global Variables
variable unsigned total_nsec = 0;

license "GPL";
author "fma";

;;

FUNCTION(_)
{
    if (enable) {
        if (total_nsec == 0) {
            out = TRUE;
            pulse = TRUE;
        }
        else {
            pulse = FALSE;
            if (total_nsec >= (1000000000 / freq / 2)) {
                out = FALSE;
            }
        }

        total_nsec += period;
        if (total_nsec >= (1000000000 / freq)) {
            total_nsec = 0;
        }
    }
}

Please Log in or Create an account to join the conversation.

fma
Offline
Senior Member

17 Oct 2011 08:01 - 17 Oct 2011 08:09 #13966 by fma

Replied by fma on topic Re:Threads

Oups, there is an issue in the previous code: I inverted the frequency computation...

Anyway, here is a new version, using fp, allowing freq. < 1:

component clock "Generate a clock signal";

pin in bit enable=TRUE "enable clock";
pin out bit out=FALSE "50% duty cycle clock output";
pin out bit pulse=FALSE "pulse clock output";
param rw float freq=1000 "clock frequency";

function _ fp;

// Global variables
variable double total_sec = 0.;

license "GPL";
author "fma";

;;

FUNCTION(_)
{
    if (enable) {
        if (total_sec == 0.) {
            out = TRUE;
            pulse = TRUE;
        }
        else {
            pulse = FALSE;
            if (total_sec >= (2. / freq)) {
                out = FALSE;
            }
        }

        total_sec += fperiod;
        if (total_sec >= (1. / freq)) {
            total_sec = 0.;
        }
    }
}

Last edit: 17 Oct 2011 08:09 by fma. Reason: Changed total_sec from float to double

Please Log in or Create an account to join the conversation.

Time to create page: 0.170 seconds