DRV8434A: How to use DRV8434 Driver IC to control stepper motors

Tool/software:

I have 2 questions about utilizing the DRV8434 driver IC to control a stepper motor, the questions are as follows:

1. Using DRV8434 to drive a stepper motor, how can I make the stepper motor return to the home position first after power up without a sensor?

2.My motor is rotating up and down, why is it easier to generate a stall signal from STL_REP PIN when rotating up, but not to generate a STALL FAULT signal from STL_REP PIN when rotating down?

3.Is it possible to design the circuit without using TRQ_CNT/STL_TH? If I don't use this PIN, will it prevent me from detecting STALL and FAULT?