DRV8825, stepper not step

Hello, i used my drv8825 to control iac driver, at last time when i used drv8825 it worked, but now it not send signal to step motor, and all input signals works correctly. I used a simple scheme to connect drv8825 where reset and sleep connecting to logic supply. Logic supply 3.3v, stepper used 12v, vref 0.9v.
Can you give me some ideas to test my drv8825? How i can know drv8825 died?

Hello.

Can you post pictures that show your stepper driver and your connections to it including any soldered connections? The driver should work with a 3.3V logic supply, but your VREF corresponds to a current limit of 1.8A, which is generally above what we expect this driver board to work at without additional cooling. Can you try the driver with the current limit below 1.5A (VREF = 0.75V)?

-Nathan