L297 stepper driver help

Hi All

I need to put L297 stepper driver in 'wave drive mode' permanently. I connect HALf/FULL pin 19 to GND but it work in 'NORMAL DRIVE MODE' by default.

I tried to connect pin 19 to low in even state and get the 'wave drive mode' on but when restart the driver it go back to 'normal drive mode'.

please i need a solution to stand on 'wave drive mode' permanently.