Pin interface definition: (It is recommended to use a 2mm spacing row pin connector for the interface)

VCC: 5V power supply
GND: Grounding
URX: TTL serial port reception
UTX: TTL serial port transmission

You can debug and test HLK-LD1125H-2.4G on a computer through a serial port assistant.
Use any serial Debugger. Baud 115200, 8-bit data bit, 1-bit stop bit, check bit and flow control are None, and ASCII is selected for reception setting,
Select ASCII for sending settings

When the radar detects significant motion, it outputs mov，dis=***.
When the radar detects a stationary state or small amplitude movement of the human body, it outputs occ，dis=***.
When the radar cannot detect the target, it stops outputting. Users can set a certain delay in the upper layer to avoid frequent unmanned states when weak signals are present.

Rmax=* *, set the maximum detection distance. The distance value of one decimal place can be set, in meters. For example, setting the module to only detect targets within a distance of 6 meters. Then send rmax=6, and the module will only output targets within 6 meters. Targets 6 meters away will not output. The default rmax for the module is 6.

Mth1_ Mov=xx: Set the motion detection threshold within 2.8 meters, with a default value of 30

Mth2_ Mov=xx: Set the motion detection threshold within 2.8~8 meters, with a default value of 15

Mth3_ Mov=xx: Set a motion detection threshold of over 8 meters, with a default value of 6

Mth1_ Oc=xx: Set a detection threshold within 2.8 meters, with a default value of 30

Mth2_ Oc=xx: Set a detection threshold within 2.8~8 meters, with a default value of 15

Mth3_ Oc=xx: Set a detection threshold above 8 meters, with a default value of 6

Save to save the settings. Otherwise, the default value will be restored after power failure.

Get_ All, obtain the current parameter settings.