Hi,
I've been recently working on trying to stablish an i2c (twi) communication between my nrf52 Dev kit and a LIS3DH located in a STEVAL-IDI-003V2 board.
In this post https://devzone.nordicsemi.com/f/nordic-q-a/34710/lis2dh12-driver-issue-in-nrf-sdk-v15-0 @lhochstetter shared a successful code (thank you!).
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Right now, for me the code compiles without any errors and when loaded to the board, I get
<info> app: Identity: 0
on a PuTTY terminal.
I guess I should see the value 33, as it is the default value stored on the 0x0F WHO_AM_I register of the sensor. Am I right?
Using a osciloscope I see that the communication sequence is: [ Start - 0x19 WR - NAK - Stop ]. The 0x19 register is the first register the master writes to. In lis2dh12.h there appears
#define LIS2DH12_BASE_ADDRESS_LOW 0x18U #define LIS2DH12_BASE_ADDRESS_HIGH 0x19U
Looking at both lis2dh12 and lis3dh datasheets the registers are almost the same, and I know the 0x19U is the default address configured in the lis3dh driver. Looking at the sequence, 0x19 WR seems logical. The thing is I am not getting a response from the sensor, therefore it's no surprise to see the "Identity: 0" message on PuTTY.
I am using the lis2dh12 library but the lis3dh sensor. This may seem a problem but I can't see why it wouldn't work, as the registers that I am addressing are the same I would be addressing if I was using a lis2dh12 sensor.
Previously I tested another STEVAL-IDI003V2 sensor and I got some weird values from the sensor, but there was an existing communication between the board and the sensor. I haven't changed the wiring.
Do you think I've made a mistake using the lis2dh12 library? If so, why? Is there anything else I can check/do to solve my problem? May the sensor be damaged?
Thank you in advance,
LFanals