2021-07-21 06:54 PM
I am using the LIS3DH MEMS motion sensor. To generate interrupts when motion exceeds a threshold, I need to set certain flags in the INT1_CFG register (address 0x30). The manual says: Write operation at this address is possible only after system boot.
What exactly does this mean? Does it mean I can only write to this address once per time I power on the LIS3DH? Does it mean I have a window of time to write to INT1_CFG after it powers on? If I want to write to it multiple times eg. to change interrupt configuration, do I need to fully power cycle the device?
Thanks.
2021-07-22 06:20 AM
Hi, in the LIS3DH datasheet (https://www.st.com/resource/en/datasheet/lis3dh.pdf) p.32 there is: "The boot procedure is complete about 5 milliseconds after device power-up". So you should wait 5ms only once after the start up of the device, before I2C/SPI, but no need to reboot the device every time you want to change register configurations.
You can also decide to read/write multiple registers using the MS bit at ‘1’.
Tom