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how to expand pwm pins?

Hi
i'm a beginner in MCUs world .
i'm facing some issues ...
in LPC17XX datasheet there are 6-output general purpose PWM available in LPC1768 I'm planning to use 7 PWM pin to control the speed of 7 BLDCs by ESCs
but i need one more PWM pin .(i need them separately)

sometimes it happen that some more pin of a kind are required separately(i mean asynchronous) do you have any idea how to solve this problem ?
by the way this micro has one specialized motor control PWM can i use it for 7th one ?
i may also need some more PWM pins for 2 or 3 DC motors (synchronous) .

I've found out that one expanding way is using multiplexers for synchronous buses .
one more way that i saw pple used with arduino was Latch method and shift register method ( in this method they use 74Hc595 )....
but they have their own difficulty ....

Parents
  • Because PWM is a hardware feature of the chip, you cannot change it.

    If you need more pins with hardware PWM capability, then you will just have to search for a different chip which has that hardware.

    Or you can add external hardware; particularly for motor control, there are chips which can do the PWM for you...

    Or you may be able to do the PWM in software - eg, using a timer interrupt to give the timing

Reply
  • Because PWM is a hardware feature of the chip, you cannot change it.

    If you need more pins with hardware PWM capability, then you will just have to search for a different chip which has that hardware.

    Or you can add external hardware; particularly for motor control, there are chips which can do the PWM for you...

    Or you may be able to do the PWM in software - eg, using a timer interrupt to give the timing

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