Ultrasonic Sensor (SEN0591)

I am working with some of these sensors I got recently.

https://wiki.dfrobot.com/Ultrasonic_Ranging_Sensor_3m_SKU_SEN0591 

https://www.dfrobot.com/product-2728.html

And they work great, but I'm trying to use the switch polarity mode instead of distance mode and I'm struggling to get it working. The wiki seems incomplete, and there doesn't seem to be a register dedicated to reading the switch mode. I can change these two registers below all I want, but the reading continues to spit out mm values:

What is the correct process for reading the switch value output?