BLE stack using PPI channels #ble #nrf52832


robert.konc@...
 

In my application I was try to use 6 PPI channels. And I discovered that almost all channels is used by BLE stack.
NRF52 chip have dedicated PPI [20:31] channels for radio. Why this challens was not used by BLE stack.
Is three any posibilities to change this?

Thanks in advance!

Br,
Robert


Sebastian Boe
 

Good question, there exists an issue that can be used for this discussion:

https://github.com/zephyrproject-rtos/zephyr/issues/7092

________________________________________
From: devel@... <devel@...> on behalf of robert.konc@... <robert.konc@...>
Sent: Wednesday, September 26, 2018 12:33:18 PM
To: devel@...
Subject: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

In my application I was try to use 6 PPI channels. And I discovered that almost all channels is used by BLE stack.
NRF52 chip have dedicated PPI [20:31] channels for radio. Why this challens was not used by BLE stack.
Is three any posibilities to change this?

Thanks in advance!

Br,
Robert


Carles Cufi
 

Hi Sebastian, Robert,

Sebastian, thanks for pointing out the existing issue.
Robert, would you please comment on that issue stating the needs of your application so we can evaluate how best to fix this and we can also include you in upcoming Pull Request reviews so you can make sure we've addressed it in a way compatible with your requirements?

Andrzej, Vinayak: We should revisit this as soon as possible. Is DTS an option here? I assume not since this is an nRF-specific hardware resource.

Carles

-----Original Message-----
From: devel@... <devel@...> On
Behalf Of Sebastian Boe
Sent: 26 September 2018 12:36
To: robert.konc@...; devel@...
Subject: Re: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

Good question, there exists an issue that can be used for this
discussion:

https://github.com/zephyrproject-rtos/zephyr/issues/7092

________________________________________
From: devel@... <devel@...> on
behalf of robert.konc@... <robert.konc@...>
Sent: Wednesday, September 26, 2018 12:33:18 PM
To: devel@...
Subject: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

In my application I was try to use 6 PPI channels. And I discovered that
almost all channels is used by BLE stack.
NRF52 chip have dedicated PPI [20:31] channels for radio. Why this
challens was not used by BLE stack.
Is three any posibilities to change this?

Thanks in advance!

Br,
Robert



Chettimada, Vinayak Kariappa
 

Hi,

The pre-programmed PPI are very specific to Nordic's in-house stack implementation needs. Some of them coincidentally can be re-used in Zephyr implementation.
I will try to send a PR by EOD, if its doing in few minutes. Else, assume that it’s a bit more work.

Regards,
Vinayak

-----Original Message-----
From: Carles Cufi <Carles.Cufi@...>
Date: Wednesday, 26 September 2018 at 12:53 PM
To: "Bøe, Sebastian" <Sebastian.Boe@...>, "robert.konc@..." <robert.konc@...>, "devel@..." <devel@...>
Cc: Andrzej Głąbek <Andrzej.Glabek@...>, "Chettimada, Vinayak Kariappa" <vinayak.kariappa.chettimada@...>
Subject: RE: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

Hi Sebastian, Robert,

Sebastian, thanks for pointing out the existing issue.
Robert, would you please comment on that issue stating the needs of your application so we can evaluate how best to fix this and we can also include you in upcoming Pull Request reviews so you can make sure we've addressed it in a way compatible with your requirements?

Andrzej, Vinayak: We should revisit this as soon as possible. Is DTS an option here? I assume not since this is an nRF-specific hardware resource.

Carles

> -----Original Message-----
> From: devel@... <devel@...> On
> Behalf Of Sebastian Boe
> Sent: 26 September 2018 12:36
> To: robert.konc@...; devel@...
> Subject: Re: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832
>
> Good question, there exists an issue that can be used for this
> discussion:
>
> https://github.com/zephyrproject-rtos/zephyr/issues/7092
>
> ________________________________________
> From: devel@... <devel@...> on
> behalf of robert.konc@... <robert.konc@...>
> Sent: Wednesday, September 26, 2018 12:33:18 PM
> To: devel@...
> Subject: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832
>
> In my application I was try to use 6 PPI channels. And I discovered that
> almost all channels is used by BLE stack.
> NRF52 chip have dedicated PPI [20:31] channels for radio. Why this
> challens was not used by BLE stack.
> Is three any posibilities to change this?
>
> Thanks in advance!
>
> Br,
> Robert
>
>
>


Chettimada, Vinayak Kariappa
 

Hi,

Only 5 of the pre-programmed PPI can be reused in Zephyr's BLE implementation. But the task to refactor the controller is not simple (i.e. not doable in a day or two).

In upstream Zephyr, PPI's 16,17, 18 and 19 are free for nRF52832. And additionally, 14 and 15 are free if PA/LNA is not enabled.

Regards,
Vinayak

-----Original Message-----
From: "Chettimada, Vinayak Kariappa" <vinayak.kariappa.chettimada@...>
Date: Wednesday, 26 September 2018 at 1:02 PM
To: Carles Cufi <Carles.Cufi@...>, "Bøe, Sebastian" <Sebastian.Boe@...>, "robert.konc@..." <robert.konc@...>, "devel@..." <devel@...>
Cc: Andrzej Głąbek <Andrzej.Glabek@...>
Subject: Re: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

Hi,

The pre-programmed PPI are very specific to Nordic's in-house stack implementation needs. Some of them coincidentally can be re-used in Zephyr implementation.
I will try to send a PR by EOD, if its doing in few minutes. Else, assume that it’s a bit more work.

Regards,
Vinayak

-----Original Message-----
From: Carles Cufi <Carles.Cufi@...>
Date: Wednesday, 26 September 2018 at 12:53 PM
To: "Bøe, Sebastian" <Sebastian.Boe@...>, "robert.konc@..." <robert.konc@...>, "devel@..." <devel@...>
Cc: Andrzej Głąbek <Andrzej.Glabek@...>, "Chettimada, Vinayak Kariappa" <vinayak.kariappa.chettimada@...>
Subject: RE: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832

Hi Sebastian, Robert,

Sebastian, thanks for pointing out the existing issue.
Robert, would you please comment on that issue stating the needs of your application so we can evaluate how best to fix this and we can also include you in upcoming Pull Request reviews so you can make sure we've addressed it in a way compatible with your requirements?

Andrzej, Vinayak: We should revisit this as soon as possible. Is DTS an option here? I assume not since this is an nRF-specific hardware resource.

Carles

> -----Original Message-----
> From: devel@... <devel@...> On
> Behalf Of Sebastian Boe
> Sent: 26 September 2018 12:36
> To: robert.konc@...; devel@...
> Subject: Re: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832
>
> Good question, there exists an issue that can be used for this
> discussion:
>
> https://github.com/zephyrproject-rtos/zephyr/issues/7092
>
> ________________________________________
> From: devel@... <devel@...> on
> behalf of robert.konc@... <robert.konc@...>
> Sent: Wednesday, September 26, 2018 12:33:18 PM
> To: devel@...
> Subject: [Zephyr-devel] BLE stack using PPI channels #ble #nrf52832
>
> In my application I was try to use 6 PPI channels. And I discovered that
> almost all channels is used by BLE stack.
> NRF52 chip have dedicated PPI [20:31] channels for radio. Why this
> challens was not used by BLE stack.
> Is three any posibilities to change this?
>
> Thanks in advance!
>
> Br,
> Robert
>
>
>


robert.konc@...
 

Hi Charles

We need 6 PPI channels to drive BLDC motor.
For now I'm modify radio_nrf5_ppi.h. So I could work.
File si also attached.
In begginig of file is  #define CONFIG_BT_NRF52X_RADIO_EVENT_TIMER which enable to use predefine PPI's.