C
Calum MacLean
- Jan 1, 1970
- 0
Hi
I hope I'm mailing this to the right group.
My company has a piece of hardware which, among other things, is intended to
provide measurements of the frequency of a clock signal (typically a few
MHz).
To do this, it will measure the number of rising clock edges in a period of,
say, 10us (which time period is measured using a system clock running at a
higher frequency - say 100MHz or so).
So, we will end up with the number of rising clock edges in every 10us, and
from this the clock frequency is to be calculated. The aim is also to track
the frequency as it changes over time.
My question is, what is the best way to calculate the clock frequency at a
particular point? Are there standard statistical/numerical methods which
can be used for this?
Obviously, you can get a rough measurement of the frequency over a short
time - the 10us. And you can get a more precise measurement over a longer
period of time, but then the time resolution is not very accurate.
Are there techniques which can be used to calculate a value, with an error
range, for the frequency at any point in time?
So you could plot the frequency against time, with a given error.
Note also that there would also be an error in the system clock measuring
the 10us period, so this would also have to be taken into account.
I'd note that I'm neither a hardware engineer, nor a mathematician, so I
hope what I've described above makes sense.
Thanks for your help!
Calum
I hope I'm mailing this to the right group.
My company has a piece of hardware which, among other things, is intended to
provide measurements of the frequency of a clock signal (typically a few
MHz).
To do this, it will measure the number of rising clock edges in a period of,
say, 10us (which time period is measured using a system clock running at a
higher frequency - say 100MHz or so).
So, we will end up with the number of rising clock edges in every 10us, and
from this the clock frequency is to be calculated. The aim is also to track
the frequency as it changes over time.
My question is, what is the best way to calculate the clock frequency at a
particular point? Are there standard statistical/numerical methods which
can be used for this?
Obviously, you can get a rough measurement of the frequency over a short
time - the 10us. And you can get a more precise measurement over a longer
period of time, but then the time resolution is not very accurate.
Are there techniques which can be used to calculate a value, with an error
range, for the frequency at any point in time?
So you could plot the frequency against time, with a given error.
Note also that there would also be an error in the system clock measuring
the 10us period, so this would also have to be taken into account.
I'd note that I'm neither a hardware engineer, nor a mathematician, so I
hope what I've described above makes sense.
Thanks for your help!
Calum