VL53L1X Interrupt not working, No measurements

[AVR_embedded]

Hi, I am having trouble with the interrupt. I manange to coummunicate via I2C and read Model ID and Type. But my problem is that i can't initiate the sensor via the VL53L1X_SensorInit() function in the Ultra Lite Driver I'm using. When I debug I see that the program gets stuck in the wait for new data from the sensor in VL53L1X_CheckForDataReady(). In this function the polarity of the interrupt is read as 0x00 and the GPIO__TIO_HV_STATUS as 0x03. Bit 0 in GPIO__TIO_HV_STATUS and the interrupt polarity must be equal for the program to interpret this as data is ready (i.e. a measurement has been made and can be read). A strange thing is that the interrupt polarity is 0x00 (active low) by default even if the manual says active high. And if I try to set the polarity to active high using the dedicated function it will still be active low. If I plug in a logic analyzer I can see that the GPIO1 (Interrupt output) from the sensor is high all the time. I then tested the sensor with the Arduino library and code and it worked fine and I could see the shift in GPIO output first time i tried it. Thereafter however it still produced distance values but I could not see the shift in GPIO level. The GPIO was high all the time.

Could someone please help me with this? It is part of a school project which I have to finish soon... :)

THANK YOU!

*****************************************************************************************************************************

setup_i2c();

// Reset Sensor
status = VL53L1_WrByte(dev, SOFT_RESET, 0x00); //Reset
_delay_ms(100);
status = VL53L1_WrByte(dev, SOFT_RESET, 0x01); // Exit Reset
_delay_ms(1000);

// Wait for sensor boot
while(sensorState == 0){
status = VL53L1X_BootState(dev, &sensorState);
_delay_ms(10); // 10 msec delay
}

/* Those basic I2C read functions can be used to check your own I2C functions */
status = VL53L1_RdByte(dev, 0x010F, &byteData);
//printf("VL53L1X Model_ID: %X\n", byteData);
status = VL53L1_RdByte(dev, 0x0110, &byteData);
//printf("VL53L1X Module_Type: %X\n", byteData);
status = VL53L1_RdWord(dev, 0x010F, &wordData);
//printf("VL53L1X: %X\n", wordData);

VL53L1X_SetInterruptPolarity(dev, 0x01);
_delay_ms(1000);
VL53L1X_GetInterruptPolarity(dev, &int_pol);

/* Init VL53L1X */
VL53L1X_SensorInit(dev);

************************************************************************************************************

VL53L1X_ERROR VL53L1X_SensorInit(uint16_t dev)

{

VL53L1X_ERROR status = 0;

uint8_t Addr = 0x00, tmp;

for (Addr = 0x2D; Addr <= 0x87; Addr++){

status |= VL53L1_WrByte(dev, Addr, VL51L1X_DEFAULT_CONFIGURATION[Addr - 0x2D]);

}

    VL53L1X_GetInterruptPolarity(dev, &tmp);    // ADDED CHECK!!

status |= VL53L1X_StartRanging(dev);

tmp  = 0;

while(tmp==0){

status |= VL53L1X_CheckForDataReady(dev, &tmp);

}

status |= VL53L1X_ClearInterrupt(dev);

status |= VL53L1X_StopRanging(dev);

status |= VL53L1_WrByte(dev, VL53L1_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND, 0x09); /* two bounds VHV */

status |= VL53L1_WrByte(dev, 0x0B, 0); /* start VHV from the previous temperature */

return status;

}

*********************************************************************************************************************************

VL53L1X_ERROR VL53L1X_CheckForDataReady(uint16_t dev, uint8_t *isDataReady)

{

uint8_t Temp;

uint8_t IntPol;

VL53L1X_ERROR status = 0;

status |= VL53L1X_GetInterruptPolarity(dev, &IntPol);

status |= VL53L1_RdByte(dev, GPIO__TIO_HV_STATUS, &Temp);

/* Read in the register to check if a new value is available */

if (status == 0){

if ((Temp & 1) == IntPol)

*isDataReady = 1;

else

*isDataReady = 0;

}

return status;

}

[Zhiyuan.Han]

Hi 

Few things worth to check for your problem.

1. Check if the sensor is really working by taking a video with a non-apple phone, if the sensor start working, the camera could capture the VCSEL light. 
2. Maybe some I2C function was not well implemented, I2C bus read and write functions, I attached a guide, you can validate you I2C bus function are all correct. 
3. Sensor side GPIO configuration, the interrupt pin is open-drain GPIO, you need pull-up with a 47K resistor. 
4. The host side GPIO configuration, below is an example from STM32 F401 example code.
5. Follow the UM and example code in the link:X-CUBE-53L1A1 - Long Distance Ranging sensor software expansion for STM32Cube - STMicroelectronics

Br

Zhiyuan.Han

[AVR_embedded]

Hi, and thank you for your reply.

I checked the things on your list:

1. I couldn't see any light in a slow motion video, but I know it's working with the Arduino code as I mentioned.

Maybe I will try it with the Arduino code.

2. The I2C read/write functions are working properly which I have seen with a logic analyzer.

3. The sensor is mounted on a breakout board with a 47k pull-up resistor.

4. I'm a little bit unsure about this part but I don't read the GPIO1 from the sensor with the MCU. I monitored it with the logic analyzer.

5. I used an example code from the beginning when creating my program and it's almost identical to mine.

I plugged in the analyzer again and I saw that the default configuration with address 0x30 = 0x01 (INT active high) was written together with the rest of the configuration to the registers. But when calling VL53L1X_GetInterruptPolarity() from VL53L1X_CheckForDataReady() it returns polarity 0 and reads 0x31 = 0x03 which means that interrupt is active low and interrupt is currently high (bit 0 in 0x31).  

[Zhiyuan.Han]

Hi 

Your issue seems quite strange, please check your hardware connection, or change a new module to try.

• The default configuration with address 0x30 = 0x01 (INT active high), no problem here.
• When calling VL53L1X_GetInterruptPolarity() from VL53L1X_CheckForDataReady() it returns polarity 0 . here is something went wrong.  sensor was not able to change the setting by himself.  
•  reads 0x31 = 0x03; With default interrupt active high setting, no problem. 

Br

Zhiyuan.Han