That is a fabulous result! I think I would do the same thing, take the 1000 readings non- interrupt based. See how accurate it is, otherwise take 2000 samples, or 3000 which will only take 0.5 seconds.
Let us know the result, measure sine waves, triangular waves and square waves. Michel On Jun 5, 11:42 pm, Tobias <[email protected]> wrote: > David: I am using the INA219 averaging at 128 samples. It is a very > good feature indeed. We are trying to get a library together with all > the functions so we can switch back and forth between some of the > features depending on what is being read from it. > > Michel: Tests are done! I found a faster way to do the i2c. And your > math worked great reducing processing time! > I tried to run the encoder function once in a while but it did not > work. Lets say was a mistake not to put a interruption pin on my IO > header. > > Just i2c get bus voltage: 193 ms > Using sq() function: 388 ms > Using z*=z then summing: 196 ms > Including encoder z*=z: 207 ms > > At 207 ms for a thousand readings we have 4.8 kHz, or 80 points for a > 60Hz sine. =) > I think I will finish up the code and try to take some measurements. > > You say doing time interrupt is going to slow this down. What about > counting all the 1000 readings and dividing by the time it took to > make them? Not a good idea? > > Tobias > > On 5 jun, 04:14, Cobra007 <[email protected]> wrote: > > > > > > > > > > The way to do this properly, as in how a real DMM does it, is to use a > > > dual-slope converter that will produce a useful number with every sample. > > > > These successive approximation converters that are common as dirt these > > > days are just not very good at the job of converting a signal and > > > producing a useful number. > > > > -- > > > David Forbes, Tucson AZ > > > DMMs with true RMS measurements have been discussed here before, but > > the only proper way to measure true RMS is by following it's > > definition. > > > My DMM is also true RMS, but really, any DC voltage shows as 0V RMS > > which is by definition incorrect. Leaving out the DC component means > > including a high pass filter, but they are not ideal, so for any > > frequency below the specified frequencies, you cannot rely on the RMS > > reading. Following this integral and squaring method should produce a > > reliable reading from 0Hz up to a certain frequency. > > > Michel -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
