TIDA-010031: TIDA-010031 Schematic clarification

Hello,

I need some clarification on TIDA -010031 schematic for following question:

1) In schematic U_BEMF,V_BEMF,W_BEMF,BEMF_C is connected to ADC(A7,A6,A5,A4) pin no 31,32,33,34 respectively but resistors divide network one end should be connect to Gnd for measurement , but in schematic it is not there .

what is the reason behind this and how the U_BEMF,V_EMF,W_BEMF measured ?

2) Again in schematic W_BEMF,U_BEMF,BEMF_C is connected to pin 41,10,37 of controller . Pin 41 and 10 is either act as GPIO or Comparator input. And pin 37 either act as GPIO or Opamp 3 output as per controller MSP430FR2355 datasheet 

what is the reason  and logic behind this?

3) How U_ctrl,V_Ctrl and W_Ctrl (Pin 45, 36, 35 respectively) is sensed by controller without any GND reference and why we need this ?

Please find the Schematic with highlighted

Thanks & Regards

Dhiren SahooSchematic queries for highlighted point.pdf