How to modify the timing at TWIM write/read sequence?

RE: How to modify the timing at TWIM write/read sequence?

Einar Thorsrud — Wed, 24 Jan 2024 09:39:17 GMT

Hi Jeff,

I see. Did the sensor vendor say more about what caused problems for the sensor? An alternative could be to split up the sequence in several transactions and add a delay in software (with a k_sleep()) between them to ensure they are long enough, if that is indeed what casues the problem for the sensor.

RE: How to modify the timing at TWIM write/read sequence?

Jeffery — Wed, 24 Jan 2024 01:38:52 GMT

Hi Einar

Thanks. I2C frequency was the lowest(100K). The result was same.

Jeff

RE: How to modify the timing at TWIM write/read sequence?

Einar Thorsrud — Tue, 23 Jan 2024 12:34:23 GMT

Hi,

It seems like the sensor id doing some clocke stretching, so this time (before the snesor answers) is dictatedby the sensor, and not the nRF. If it needs a longer pause before answering, why does it not just stretch the clock longer? If this is the problem, then it seems like the sensor is behaving strangely.

Can you try to work around it by using a lower I2C frequency?

RE: How to modify the timing at TWIM write/read sequence?

Jeffery — Tue, 23 Jan 2024 09:23:11 GMT

Sorry. I posted same waveforms 3 times.