Hi Guys I'm new to mbed coding and I'm facing certain difficulties while using PwmOut (pin 22). Couple of regular members suggested me to post my problem in here.

So by using PwmOut(p22) , I want to generate 200 kHz square wave and from that wave I need 1kHz square wave.

I got very limited time to finish this stuff and I seek help from you guys.

I have tried to make a code and below is the picture;

Anyone Please...

Well I made some improvement. I used a code as shown below and I got square wave of 200kHz with 50% duty cycle.

Hi Chris, let me test this on oscilloscope. I will get back to you in few mins.

Chris

Actually from 200 kHz wave , I need 1 kHz perfect square wave.

I have tested this code on oscilloscope and I got 200 kHz. But what I require is 1 kHz square wave from 200 kHz wave.

Nothing appeared with this....

I dont need frequency modulation.

All I need is 1KHz square wave from 200 kHz wave.

What kind of 1kHz square wave do you need? If you just need a 1kHz square wave, what has 200kHz to do with it? A 1kHz square wave = 1kHz square wave, there is nothing related to another frequency in it. So you first need to make clear what that 1kHz wave must be, not square apparantly. Maybe upload a drawing of what it is supposed to look like.

That's a 1kHz square wave.

200kHz/1Khz = 200 Cycles.

As a I said before, From 200kHz square wave, I want to generate 1kHz square wave.

Your picture doesn't work.for me.

Edit: I can do a guess? Should it be 100 cycles 50% duty cycle, then 100 cycles 0% duty cycle? Which would be on-off keying of the 200kHz carrier. (And not the same as 1kHz square wave).

I got it.

1. include "mbed.h"

PwmOut PwmPin (p22);

int main() { PwmPin.period(0.000005); Set frequency to 200,000 Hz (period = 5 us)

while(1){ infinite loop PwmPin.write(0); Set the duty cycle to 0%

wait_us(500); wait 100 PWM cyles

PwmPin.write(1); Set the duty cycle to 100%

wait_us(500); wait 100 PWM cycles } }

Thank you Erik and Chris.You guys been so helpful... :)

(y)

Yea that's what it was.. :). Doing this coding stuff is really frustrating. lol

Guys I'm further working on the same code and trying to generate sine wave ( 1kHz) from it.