DRDY INT1 can't be disabled on IIS2DLPC

[dawime]

I got a STEVAL-MKI191V1 Eval, and I am trying to write a wake-up driver for the accelerometer, but I cannot seem to disable the DRDY interrupt on INT1. I am writing 0x20 to register 0x23 (CTRL4_INT1_PAD_CTRL), but when looking at the scope, I see the ODR rate programmed outputted no matter what I try. I can read-back the register, and I see its not set, but it does not seem to matter to the INT1 output.

Any idea of what might be going on? Does that register only work in High power mode? I am trying to work at 12.5Hz LP mode. Thanks

[Miroslav BATEK]

Please share you complete sensor configuration.

If you write 0x20 to register CTRL4_INT1_PAD_CTRL (23h) the DRDY is disabled.

[dawime]

Miroslav, thanks for the reply. It seems rebooting the part fixed the problem. Not sure why, but I'll keep an eye on it. Also, since you work for ST, there are several typos in the register description section of the IIS2DLPC datasheet (DocID031788 Rev 3). Specifically The binary address for Y_OFS_USR, Z_OFS_USR and CTRL7 registers are wrong (page 46).

Another question for you - I am planning on using the activity monitor to interrupt the processor to go do something, and start collecting data. since my data collection is planned at 12.5Hz in LP1, from a power consumption perspective on the accelerometer there really isn't any advantage, since the mode I am going to after wake up is the same as the one I was in sleep mode, correct? I will have some gains on the processor side from only having to wake up after I get an interrupt, but I believe the consumption will stay at around 1uA

Thanks

Daniel

[Miroslav BATEK]

Thank you @Community member​ , I will ask for the correction of typo errors.

Concerning you question, yes there is no benefit in sleep mode if you use the data rate 12.5Hz, it would be useful only if you need higher data rate when the sensor is waked up.