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13 years, 1 month ago.
I want a phase shift between two PWM signals.
I want to generate two PWM signals, which are phase shifted by 90. For phase shifting I had used "wait" command, but it is not working.Program that i had written is shown below:
- include "mbed.h"
PwmOut a(p21); PwmOut b(p22);
int main() { a.period_us(10); b.period_us(10); while (1){ a.pulsewidth_us(2);
wait_us(2); b.pulsewidth_us(2);
} }
Question relating to:
2 Answers
13 years ago.
PWM on the LPC1768 is always in phase since there is only a single PWM timer. I think with dual slope option you can get it out phase, but the mbed library does not support that by default.
13 years ago.
The period of the wave form is 10 uSec. Thus, for 90 degree phase difference, the wave forms should be seperated in time by 2.5 uSec and not 2 as in your code.