I2C clock frequency problem

[Manjunath K S]

Hi,

I am using NRF52832 development board , to which i have interfaced LIS3DSH accelerometer sensor(3.3V i2c)

when i  configure it for 1600 sampling rate and all the axis enabled , i am not able to get any data .

could anyone help with this problem.

also the I2c clock frequency, as shown in below image, while i am capturing data when i observe in oscilloscope or logic analyzer , clock frequency is showing 200 all the setting is for 400KHz.

what could be the problem for this or is there any other way i need to follow to set the clock to 400KHz.

help me ASAP...

Thank you

[haakonsh]

"also the I2c clock frequency, as shown in below image, while i am capturing data when i observe in oscilloscope or logic analyzer , clock frequency is showing 200 all the setting is for 400KHz."
That's unlikely, I think you're measuring the clock frequency incorrectly.


Why have you enabled pulldowns on your IO pins?

[Manjunath K S]

actually that's not the part of code , sorry excluding that is the actual code

[Manjunath K S]

without slave device about 400 k clock i am able to see, when i connect a slave device its dropping to 200 k

[awneil]

It is a standard feature of the I2C bus that it operates at the speed of the slowest attached peripheral

[Manjunath K S]

tqs  awneil but peripheral supports 400K clock

[awneil]

But your test demonstrates that the issue is not to do with your software configuration, or an SDK bug, in the nRF chip?

Does your peripheral default to 200kHz, and need to be configured to change to 400 ... ?

[Manjunath K S]

By default lis3dsh peripheral will support 400K fast mode, it was working in other development kit(also clock in other dk was also reflected) like renesas and stm eval board.

that's  y i didn't get to know the actual problem and asking for your help.