LD2415H unable to change configurable parameters

Question

I have an LD2415H, and I have a couple of questions:

(1) The documentation says that both the red and green LEDs should flash three times upon power-up, but this doesn't happen with mine. Only the green LED flashes, and I have never seen the red LED flash even once.

(2) I can't seem to change any of the configurable parameters. When I send the command (using either my own software or HLK's Windows app) to change the speed units to MPH, KPH, or MPS, the speed measurement coming from the radar does not change. For example, if I move a target toward the radar at exactly 5 mph, the device sends "V+008.0" which implies it's measuring KPH. If I send the command to change speed units to KPH, the value still comes back "V+008.0" and if I send the command to change speed units to MPS, the value still comes back "V+008.0"
When I set the speed range lower limit to 5, I still see speed measurements below 5 coming from the radar. Shouldn't it be filtering out anything below 5? It appears as though the device isn't actually applying any config changes, and is stuck at factory defaults.

born.fight.die · Answer

Hello, man.

I don't have an answer to your question, but. The HLK software is very raw. When I was playing with ld2420, I found out that the documentation is not accurate, and the syntax of USART messages is VERY different from what is documented. And the logic of the module's interaction with the software is also very different.

Theoretically, it should send a packet with detection data every 100 ms and wait for a command to switch to configuration mode.
In reality, it constantly sends an “I'm here” packet from the start and waits for a response from the program. Only after receiving a response does it start sending packets with detection data.

There are differences in the header and tails.

The only way you can figure this out is to attach and run a logic analyzer to UART pins, and look at the REAL UART packets and the module's response to them...

Tim · Answer

Thanks for the quick reply! I wasn't expecting to get any response!

admin · Answer

Dear Tim, thank you for your question, i have submit your question to our FAE, we will test to verify the question and then update to you. at the same time, could you please help to switch the data format to the standard protocol format, and then read the set parameters to see if you want to change kilometers per hour to miles per hour. Then take a screenshot and send it to us, because the upper computer can only modify the value of kilometers per hour. If you want to switch to miles, you need to enter the corresponding serial port command to modify it.following is my email, for more module issues we can talk with email: info@hlktech.com.
Sincerely waiting for your update.

LD2415H unable to change configurable parameters

3 Answers