topic Re: Speed scale parameters in AN4813 based on MC56F82748 in Digital Signal Controllers

Speed scale parameters in AN4813 based on MC56F82748

kbk — Thu, 16 Jun 2016 08:25:49 GMT

How did you get angularSpeedScale=0.6357829 and angularSpeedScaleShift=4 in the application example code of document AN4813?

Re: Speed scale parameters in AN4813 based on MC56F82748

xiangjun_rong — Mon, 20 Jun 2016 09:33:37 GMT

Hi,

Regarding your question, the angularSpeedScale/angularSpeedScaleShift are just parameter, as you know that the motor speed unit is RPM(revolutions per minute), but you just divide the edge number by tick number, so there must be a scale, the scale is related to bus clock cycle time the TMR1 counts, the total edge numbers per revolution.

I attach an1931 whiuch is written by the same author, it describes how to calculate the scale k.

Hope it can help you.

XiangJun Rong

Re: Speed scale parameters in AN4813 based on MC56F82748

kbk — Mon, 20 Jun 2016 10:11:55 GMT

Got it, thank you very much.