Re: How to change the CPU time frequency of mynewt and nimble stack

[Sterling Hughes]

Hi Jiacheng,

You need to update your newt tool along with the new develop.

Best,

Sterling

On 10 Jan 2017, at 16:46, WangJiacheng wrote:

Hi, Will,

I need more help, I have an error message when compile the target.

I’m currently working on the release branch, so upgrade to dev branch by: 1. change file project.yml from "vers: 0-latest” to "vers: 0-dev”

    2. upgrade to dev branch “newt upgrade”

Then compile the target by “newt build nrf52_boot”, an error message as:

================================================================================
Building target targets/nrf52_boot
Compiling boot.c
Archiving boot.a
Compiling bootutil_misc.c
Compiling image_ec.c
Compiling image_ec256.c
Compiling image_rsa.c
Compiling image_validate.c
Compiling loader.c
Archiving bootutil.a
Error: In file included from aes.c:29:0:

/Users/jiachengwang/dev/myproj/repos/apache-mynewt-core/crypto/mbedtls/include/mbedtls/config.h:2522:10: error: #include expects "FILENAME" or <FILENAME>

 #include MBEDTLS_USER_CONFIG_FILE
          ^
================================================================================

it seems the config file "mbedtls/config_mynewt.h” define in “crypto/mbedtls/pkg.yml” is missed.

Thanks,

Jiacheng

在 2017年1月10日，11:06，WangJiacheng <jiacheng.w...@icloud.com> 写道：

Thanks, Will.

There is an Internet connection issue to GitHub.com currently, I’ll update the code later.

Best Regards,

Jiacheng

在 2017年1月10日，10:10，will sanfilippo <wi...@runtime.io> 写道：

Hello:

This issue should now be fixed in the latest development branch. Note that this is not working on the nrf51 platforms but since you were using nrf52 it should work.

Let me know if you see any issues with it.

On Jan 8, 2017, at 6:20 PM, WangJiacheng <jiacheng.w...@icloud.com> wrote:

Hi, Will,

Thanks a lot for your reply.

Yes，the hardwear processor clock frequency of nRF52 (Cortex M4F) is 64 MHz and can not be changed.

The reason of changing CLOCK_FREQ is that I want re-use the internal timing of mynewt already there with more accurate timing, by calling function "os_cputime_get32()”. I’m trying to implement a (soft) IC card reader by nRF52 with mynewt OS and nimble stack running.

I am also considering to use an independent timer (NRF_TIMER3 or NRF_TIMER4) at the cost of about 0.1mA current. I already use NRF_TIMER2 to provide a 4 MHz clock signal output from GPIO of nRF52. By reading the source code of apache-mynewt-core, my understanding is that NRF_TIMER0 and NRF_TIMER1 is already used by mynewt OS and nimble stack, is my understanding correct?

Thanks,

Jiacheng

在 2017年1月9日，01:10，will sanfilippo <wi...@runtime.io> 写道：

Those should be the only two parameters you need to configure. Must be a bug in the controller :-)

I think it is worthwhile to point out that CLOCK_FREQ only changes the units of os cputime; it does not affect the speed at which the processor runs. At least, I could not see any other uses of CLOCK_FREQ. So, these settings only affect the nimble stack and the controller specifically (internal controller timing).

I am curious why you wanted to change this variable; what were you trying to achieve?

Thanks for pointing this out; I will take a look to see why it is not working.

On Jan 7, 2017, at 10:48 PM, WangJiacheng <jiacheng.w...@icloud.com> wrote:

Hi,

The default CPU time frequency of Mynewt OS and Nimble stack is 1 MHz, I try to change the CPU time frequency to be 2 MHz, I modified the related 2 config files:

configure file “hw/bsp/nrf52dk/syscfg.yml” as
CLOCK_FREQ:
   description: 'TBD'
   value:  2000000
configure file “kernel/os/syscfg.yml” as
OS_CPUTIME_FREQ:
   description: 'Frequency of os cputime'
   value: 2000000

The app “bleperiph" is running and the CPU time frequency is 2 MHz, also the BLE “nimble-bleprph” peripheral can be scanned by LightBlue of iOS APP, and show 1 service is there. However, when I try to connect it ,an error massage “Connection Alert: Timeout interrogating the peripheral”

When change back above 2 syscfg parameters to 1000000, it can be connected.

And app “bletiny” is the same.

Is there any missed config setting in my test? How to change the CPU time frequency to 2 Mhz and Nimble device can be connected?

Thanks,

Jiacheng