RESOLVER SOFTWARE LIBRARY TMS320F28335

Hi,

There is an example code available in control suite at

C:\TI\controlSUITE\development_kits\TMDSRSLVR_v1.0\Resolver_f28335

If you review that also, it will be easy to appreciate the implementation.

rgds,

ramesh

I kind of did that already. It helped a little but not much

The document you saw is to support the library functions.
In the code, you will see how the values are read from ADC and fed into library.

// *** Sample sine and cosine feedbacks from ADC ***
rslvrOut.sin_input = ((float)AdcRegs.ADCRESULT0*(3.0/65536.0)) - rslvrIn.offsetS; // remove opamp bias
rslvrOut.cos_input = ((float)AdcRegs.ADCRESULT1*(3.0/65536.0)) - rslvrIn.offsetC; // remove opamp bias

Basically, the signals are scaled to 3.0 to correspond to the actual signal input level.

so the sin/cosine variables have to be scaled to 0 to 3 ??

The previous provided odc by TI as the one attached I found for devices x281x or x280x explains the use of resolver lib designed including sin/cos input format, range and filter length coefficients also the use of functions involved.

But the recently provided resolver lib doc as given in C:\TI\controlSUITE\development_kits\TMDSRSLVR_v1.0\Resolver_f28335  is very vague. The algorithm used is not even mentioned to a little extent which makes it very difficult to use the library. Also, the filter used (coefficients), the sampling frequency and whether the lib requires over-sampling or under-sampling, nothing of this sort is mentioned. I believe it would be very difficult to make use of the library without these details.resolver.pdf

Within the docs folder, there is a tech paper which this implementation follows. The parameter init values can all be found in the code. Since users pick their choice of values, it is not shown explicitly in the doc, but if you look within the tech paper, doc and code, you will find more answers.

Couldn't locate the tech paper. Where is this located?

thanks for helping out.

thanks for the help ... I will use the doc to improve my system.