motor speed variable using FPGA

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you will get any frequency.

In many cases the exact pulse frequency wouldn't be as a clean clock but over a window of time it will be correct and for stepper motor it should be more than enough.

example 50MHz * 2333456/2^32 = ?

Anyway from 50MHz you cannot get exact frequencies except for cases like half/quarter etc unless you use variable analogue PLL

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you are right.

"from 50MHz you cannot get exact frequencies except for cases like half/quarter etc."

I have try s lot,but fail.I cannot get exact frequencies except for cases like half/quarter.

I will try your suggestion,hope this is average frequency really enough for stepper motor.

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you are right.

"from 50MHz you cannot get exact frequencies except for cases like half/quarter etc."

I have try s lot,but fail.I cannot get exact frequencies except for cases like half/quarter.

I will try your suggestion,hope this is average frequency really enough for stepper motor.

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No doubt you failed, despite how smart you could be. As Kaz pointed out, it is impossible to generate other than half, third, quarter... frequency, unless you accept an 'average' frequency, like in the adder solution we both presented.

That's because frequency is the inverse of period and the pwm period must necessarily be a multiple of your system clock.

In any case, for motor control a frequency in the 20-100kHz range is what is usually needed, so I don't see any problem in the frequency discretization you have in the MHz range