i am having 4 panasonic ac servo drive that accepts step signal for example if i give 1000 pulses it will rotate one 360 deg. how to set pulses in pwm . i want to control 4 servo motors simultaneously with different frequency, is this possible in pwm i am using dspic 33ep family ic it has got 12 pwm .
No.
Pwm just varies the duty cycle which will not directly control speed.
If it needs 1,000 pulses per revolution you need to change the drive frequency.
And as the previous poster says, both the pulse drive pattern, and frequency, are what you should be changing.