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TMS320F280041C: Measured speed

Part Number: TMS320F280041C

I set motorVars.flagRunIdentAndOnLine to true without a motor connected (I had 4 boards and 2 motor only). To my surprise micro somehow was able to calculate motorVars.speed_Hz. These variables ramped up to the reference motorVars.speedRef_Hz and stayed there as if a motor were connected. WHY??????? I would expect TI software to be smart enough to detect that a motor is not connected because there is no motor current. How can the software calculate speed without phase currents? I have RC circuits across FETs (drain to source). Are they somehow impersonate a motor (I do see 20mA current increase from a power supply when I flip a switch)? When a motor is connected power supply current jumps 20mA and then ramps up with the speed.