implement pedometer on ISM330IS

[apache]

Hi all,

we have a customer hardware with ISM330IS sensor on .

We want to implement a pedometer on it like in the ISM330DHCX. Is it possible ?

I followed the repo ism330is-pid/ism330is_reg.c at 413acfb51fd6f81a7449980a1caf286e37c909fe · STMicroelectronics/ism330is-pid (github.com) but it seems to not include it !

Instead I see it for ISM330DHCX (STMicroelectronics/ism330dhcx-pid: ism303dhcx platform independent driver based on Standard C language and compliant with MISRA standard (github.com)) 

Can I use that code too ?

[Federica Bossi]

Hi @apache ,

Unlike ISM330DHCX, the ISM330IS doesn't implement in the hardware the embedded function of  pedometer (step detector and step counter).

If you want to implement a pedometer you need to do it in the core.

[apache]

Hi,

thanks a lot.

What you mean in the core ? I think the HW is more or less like ISM330DHCX and even more powerful.

How to implemement in the core ? have you same example ?

Thks

[apache]

Hi ,

I saw this link here which seems to implement ISM330IS pedometer in the core (ispu-examples/ism330is_lsm6dso16is at master · STMicroelectronics/ispu-examples (github.com)) .

I have a custom MCU in my board, so do I have to downlad the pedometer.h file on the chip via I2C ?

I see the static const ucf_line_ext_t ispu_conf[] structure containg all the operation to do, Do I have to do so ? 

Of course Im going to  buy the dev kit but  I dont use ST MCU to drive the MEMS. 4

Anyway I need to validate the "production process" before I can go for production.

Can you help?

Thanks.

[Federica Bossi · Accepted solution]

Hi @apache ,

Yes, you are on the right direction.

You can follow the official driver example here where the loading of the configuration is also done:

  /* Load ISPU configuration */
  for ( i = 0; i < (sizeof(ispu_conf) / sizeof(ucf_line_ext_t) ); i++ ) {
    switch(ispu_conf[i].op) {
    case MEMS_UCF_OP_DELAY:
      platform_delay(ispu_conf[i].data);
      break;
    case MEMS_UCF_OP_WRITE:
      lsm6dso16is_write_reg(&dev_ctx, ispu_conf[i].address, (uint8_t *)&ispu_conf[i].data, 1);
      break;
    }
  }

No problem using MCUs not from ST.

[apache]

Hi Federica,

thanks for reply . I think I do more or less the same .

This is my pseudo code :

1. every time my FW start I enable the ISPU register address by writing "128" register on the 0x01H as per ISPU datasheet. 
2. I Read back this value and correctly I have "128"
3. I run more or less the same your code above in order to perform the I2C transaction and download the fw to the ISPU:

uint8_t initPedometer (){


uint8_t dataw[2];

uint32_t iteration = sizeof (ispu_conf) / 3;
uint32_t iterIsm;
for (iterIsm = 0; iterIsm < iteration; iterIsm++) {

dataw[0] = ispu_conf[iterIsm].address;
dataw[1] = ispu_conf[iterIsm].data;
if (ispu_conf[iterIsm].op == 1) {
if (I2C2_writeDelay((uint8_t)(ISPU_ADDRESS), dataw, 2)) {

return 1;

}
vTaskDelay(1); //even if I dont have to wait I wait 1 msec

} else if (ispu_conf[iterIsm].op == 2)
vTaskDelay(5); //wait 5 ms if operation is "delay"

}

return 0;
}

Please consider :

• if this method goes wrong it returns 1 otherwise 0
• Please consider Im not using your platform_write, platfomr_read since I think I dont need it , am i wrong ?

In addition is your 

sizeof(ucf_line_ext_t) equals to 3 ?

Once I have configured it I symply read 2 register starting from address 0x1C but I always get zero even if I move my board and make some steps:

while(1){

 readPEdometer();

vtaskDelay(3) ; //wait 3 sec

}

where my funciton is :

int16_t readPedometer(){

uint8_t ped=0X1C;
uint8_t result[2];
uint16_t pedL,pedH;
if (I2C2_readDelay((uint8_t)(ISPU_ADDRESS),&ped, 2, result, 2)==0){
pedL=(uint16_t)result[0];
pedH=(uint16_t)result[1];
return (pedH<<8)|pedL;

}
return -1;

}

Is this flow good or am I doing something wrong?

Thanks a lot.