VL53L7CX Some zones not updated fast enough

[FDehg.1]

We are trying to use a VL53L7CX sensor for a people counting application, but some zones won't change fast enough after a person passes through the detection field, even after a long time like 2-3 seconds. I tried resetting the sensor after each ranging, but this also takes too long (more than 1 sec). I'm using it as a 8*8 sensor and a ranging frequency of 15 Hz.

Also I'm using an esp32 as micro-controller and SparkFun_VL53L5CX arduino library, which according to the datasheet of the sensor, should be compatible with the VL53L7CX version.

Does anybody has an what the problem is, and how can I solve it?

[John E KVAM]

Thats an odd one. You tell me you are ranging at 15Hz, but are not getting updates.

So I only have questions - and not answers.

Are you using a 1M I2C speed? The sensor - by default - returns a lot of data. If you have a slow i2c speed there can be a lag.

And the sensor will stop ranging if you do not consume the data it's sending you.

At init, the sensor need to download some 83KBytes of data. So resetting it is a poor idea.

If you have $56, you can buy the EVAL kit. P-Nucleo-53L7A1. It will show you how the chip can work.

The other thing you can do is run the example code provided in the driver.

(Acutally you might look for differences between your code and the example code given in the driver. You might find some differences.)

• john

[HSche.1]

Hi FDehg.1

Did you find a working solution for the people counter? Or still facing some issues?

Regards

[John E KVAM]

IN the last weeks, ST came out with the VL53L8. It works just like the VL53L5, but due to some advanced optics it works better. Same software, although the chip has a couple more pins - so it's not hardware compatible.

But it does really 'see better'. And if one were having trouble getting the L5 or L7 to detect people due to ambient light, or a particularly dark floor the L8 would solve the problem.

• john

[imdc]

Hi John, can you help me on this - https://community.st.com/s/question/0D53W00002EuQVASA3/xnucleovl53l8a1-not-working-with-nucleof401re-and-gui

[FDehg.1]

Hi,

we tried the sensor with a STM32 dev board and there was no problem.

I don't know if the problem is from the Arduino library or the ESP32 itself.

Is there any official libraries for Arduino?

[John E KVAM]

Is there any official libraries for Arduino? No.

ST's line of several thousand different STM32 microprocessors makes it one of the worlds largest manufacturers. If I spent time creating libraries for the other brands, someone would come talk to me. And they would not be happy.

We built the code to run in 'C' on any MCU/CPU and only need to modify the I2C interface.

But then people started modifing the code - as they are allowed to do. But then I cannot maintain that code. Sorry.

• john