Scan Module and TWR Module Possible Interference Problem

[srac]

Hello,

We have a IoT edge devices based on NRF52832 with NRF SDK 17.1 with some sensors.

We are facing a problem when we are using both scanning and TWI modules together.

But both working pretty well separately.

When scanning is on sometimes my sensors can not be set as state-machine or can not sending the interrupt signal.

We only facing this problem %20 of the devices %20 of them works with low performance and others works also fine. 

Thanks,

Sirac

[Jared]

Hi there,

Can you specify what you mean by scanning? Scanning as in using the radio to look after the BLE advertising packets?

regards
Jared 

[srac]

Hi,

Yes we are scanning advertising packets and advertising at the same time.

I have discovered a new bug also.

When Scanning is on my power consumption is around 1,6 mA. After Scan is deactivated 0.1 mA.

When my led is on power consumption is around 1,4 mA. After Led is deactivated 0.1 mA.

But when I activate both power consumption goes to 6mA. Even if deactivate led power consumption still continue as 6mA. Until I turn off the scanning.

[Jared]

Hi,

Ok, lets focus on the initial problem first. You stated:

When scanning is on sometimes my sensors can not be set as state-machine or can not sending the interrupt signal.

What do you mean by setting your sensors as state machines? I'm guessing that you're trying to write to a internal register on the sensor from the nRF52 while advertising/scanning simultaneously? Which function are you using to write to the sensor and how does it not work? Does your program assert? 

regards

Jared 

[srac]

Hi,

Actually I can not log or debug at the product. I made that conclusion because if I trigger interrupt manually NRF could read the GPIO interrupt pin but again can not set the sensor's low powered state machine which triggers a interrupt.

I believe at some point my SPI buses stop working or our sensor is physically not working on some of  our devices because of mass production failures.

[Jared]

Hi,

If you can't debug the product then it's very difficult for us to investigate this issue. A general comment, there is not reason for BLE to not work with TWI simultaneously. You can find multiple posts in this forum where users have merge the TWI example in the SDK with a BLE example. 

I'm suspecting that your program asserts for some reason. Using a debugger would confirm whether it's true or not..

regards

Jared