nrfx twis drivers on nrf9160 (Zephyr)

RE: nrfx twis drivers on nrf9160 (Zephyr)

Simonr — Thu, 17 Sep 2020 07:54:44 GMT

Jagruti: I'm sorry you experienced this notification bonanza yesterday! We're looking into this right now and are working on finding out what exactly has happened here. A suggestion is to disable e-mail notifications from DevZone. This can be done by going to settings in the top right corner and uncheck the "Enable email contact" checkbox.

SE: Please create a new ticket describing your issue in detail. Feel free to link to this one if you find it relevant.

Best regards,

Simon

RE: nrfx twis drivers on nrf9160 (Zephyr)

Jagruti — Wed, 16 Sep 2020 18:34:27 GMT

Hello,

Please create a new thread. I am receiving notification of this reply every second in my mail box. I received thousands of mail in last 10 minutes. I don't know how to stop it.

RE: nrfx twis drivers on nrf9160 (Zephyr)

Smart.Enrg — Wed, 16 Sep 2020 18:11:10 GMT

Thanks Simon,

Specifically what I'm trying to do - add TWIS to Asset Tracker project.
When I look at .prj and overlay files for Thingy.91 (in Asset Tracker) - thinking since it uses I2C sensor
(though operating as TWIM), I'll at least get to see how i2c is configured there.
But other than CONFIG_*_USE_EXTERNAL=y (vs. CONFIG_ACCEL_USE_SIM=y) I do Not see any
explicit i2c config (mode, pins etc.) in .prj or overlay files.
So, my 1st question is -
a) where am I supposed to make i2c (TWIS in my case)? In order to use nrfx drivers. An example will
be great.
b) what is the correct/ recommended way of creating/ modifying project configuration - editing overlay,
.prj files directly, or from within SES > Configure nRF Connect SDK Project > menuconfig option?

Best,
SE

RE: nrfx twis drivers on nrf9160 (Zephyr)

Simonr — Mon, 14 Sep 2020 07:45:24 GMT

I would suggest using the nrfx drivers, as these are the drivers we are most familiar with. It should be possible to configure any sample project to use TWI(S) as far as I know. Do you have any specific questions on how exactly to do so?

Best regards,

Simon

RE: nrfx twis drivers on nrf9160 (Zephyr)

Smart.Enrg — Fri, 11 Sep 2020 19:10:39 GMT

[quote userid="75734" url="~/f/nordic-q-a/64482/nrfx-twis-drivers-on-nrf9160-zephyr/265874"]nRF9160 supports up to 4x I2C compatible two-wire master/slave with EasyDMA[/quote]

Thanks Simon,

Just to confirm - per quote above you are recommending using one of the unused serial slots as TWIS, using nrfx, Not Zephyr driver, right?

Browsing through various posts here on devzone and zephyr communities, what I understand about i2c-slave use on nRF9160:
a) Until ~3 weeks back Zephyr did Not have support for TWIS/ i2c slave. Though now there's "experimental" i2c slave support added to Zephyr - https://github.com/zephyrproject-rtos/zephyr/issues/27675
But nRF (including 9160) is explicitly excluded - because how EasyDMA is integral part of i2c operation -
I think Zephyr driver needs byte-by-byte access to i2c registers.

b) Per https://github.com/nrfconnect/sdk-zephyr/blob/master/include/drivers/i2c.h#L61 - it reads "The following #defines are used to configure the I2C slave device" - does that mean there's built in support for i2c_slave in current Zephyr for nRF9160? If not, what does this i2c slave device configuration is referring to/ how is it used?

Will appreciate if you could please comment on what's my best bet for realizing i2c slave on nRF9160? Also is there any example code showing i2c slave in action (nrfx perhaps)? meant for nRF9160 or nRF52.
Thanks.

Best,
SE

RE: nrfx twis drivers on nrf9160 (Zephyr)

Simonr — Mon, 24 Aug 2020 06:31:32 GMT

The nRF9160 should be able to be interfaced by an external I2C master as the nRF9160 supports up to 4x I2C compatible two-wire master/slave with EasyDMA, and the asset tracker application does not use all of these instances by default.

Best regards,

Simon

RE: nrfx twis drivers on nrf9160 (Zephyr)

Smart.Enrg — Mon, 24 Aug 2020 02:18:22 GMT

Hi Simon,

I have same use case as Jagruti - need to interface nRF9160 (running Asset Tracker app)
interfaced from/ managed by an external I2C master. So the two questions I have are:
1) Will Asset tracker application allow TWIS operation with getting into conflict with other
system resources that Asset tracker allocate by default?
2) Will 9160 respond to asynchronous queries from external/ other master in multi-master
environment? If so, then I don't necessarily need TWIS on 9160/ Asset tracker side.

Please advise. Thanks.

Best,
SE

RE: nrfx twis drivers on nrf9160 (Zephyr)

Jagruti — Thu, 13 Aug 2020 07:33:23 GMT

Hello,

No I am using separate instances for SPI and I2C (SPI3 and I2C2).

Now I have decided to use I2C master, so I can use zephyr drivers for that.

Thank you for your help.

RE: nrfx twis drivers on nrf9160 (Zephyr)

Simonr — Wed, 05 Aug 2020 06:27:00 GMT

Glad you were able to solve the initial issue. What kind of error are you seeing now then? Could it be that the I2C 0 instance is already used by the SPI or some other part of your application? The SPI and TWI can not use the same instance, as they share certain resources and therefore can not be used at the same time.

Best regards,

Simon

RE: nrfx twis drivers on nrf9160 (Zephyr)

Jagruti — Tue, 04 Aug 2020 14:14:00 GMT

Hello,

I was able to solve the above problem. I updated ncs tag to v1.2.0 and there was no compilation error.

But still TWIS is not working as expected.

nRF9160DK TWIS is interfaced to SAM's TWIM. At the same, SAM is interfaced to the sensor. SAM uses same TWIM instance but the different addresses for nRF9160DK and sensor.

When I connect SAM and nRF9160DK TWI pins, the communication between SAM and sensor is also stopped.

I don't understand what is the problem.

Because same setup works with nRF52840DK. When I use nRF52840DK as TWIS instead of nRF9160DK, everything works properly.

I just want the same functionality on nRF9160DK, but nothing works.

How should I proceed?