Beginner needing help with basic structure and pwm

RE: Beginner needing help with basic structure and pwm

Bjørn Kvaale — Mon, 12 Nov 2018 10:58:57 GMT

Could you please open a new devzone case?

RE: Beginner needing help with basic structure and pwm

Chukwuemeka — Sat, 10 Nov 2018 07:47:58 GMT

Hi Sigurd

I working on dimming two different LED strings independently (one at time) using nRF52834 SDK15. The idea is to use a high or low signal from GPIO to enable/disable a switch to one of the LED strings, and then dim the LED string that is enabled.

I have modified the ble_app_template you provided, and its working for a fixed LED string. My question is how do I modify the custom BLE service in order that I can set/clear two GPIOs before I send the PWM duty for dimming?

Thanks

RE: Beginner needing help with basic structure and pwm

Bjørn Kvaale — Fri, 13 Apr 2018 08:00:37 GMT

Take a look how the ble_blinky application does this in the ble_peripheral folder of sdk 15. The LEDs are defined in main.c:

#define ADVERTISING_LED BSP_BOARD_LED_0 /**< Is on when device is advertising. */
#define CONNECTED_LED BSP_BOARD_LED_1 /**< Is on when device has connected. */

BSP_BOARD_LED_0 & BSP_BOARD_LED_1 are defined in boards.h. I would try to understand the code & take a look at the infocenter documentation to find out how this simple example works & how the LEDs are defined.

Good luck with future development!

RE: Beginner needing help with basic structure and pwm

jmguk41 — Thu, 12 Apr 2018 20:17:54 GMT

Thanks! This works fantastic!

I changed the pin that the PWM signal is present on and my product dims almost perfectly!

Couple of questions: Sending a value of 100 turns off the output, not sure if this could be changed to a 100% duty cycle?

EDIT: FIXED THIS BY CHANGING

if(duty_cycle >= 1000)
    {
        seq_values->channel_0 = 1000;
    }

if(duty_cycle > 1000)
    {
        seq_values->channel_0 = 0;
    }

How do I change the advertising and connected LED's to different pins? The pwm pin and advertising led share the same io now and I need to move or delete the led function.

If I want to run an additional service, a custom one, do I need to write that in another file? I want to read the devices temperature, hit a button on the app and send the pwm to 0, hit again and toggle back the original pwm vale. That may be an app side job though.

I tried incorporating the custom service tutorial into the pwm example. It did not work very well. 🙂

Id like to thank you all for helping me learn this stuff and being patient with me while I fumble my way around.

RE: Beginner needing help with basic structure and pwm

Sigurd — Thu, 12 Apr 2018 14:42:33 GMT

Here is an example based on ble_app_uart + PWM driver for SDK 15. You can control the PWM duty cycle, by sending values in the range from 0 to 100, either using nRF Toolbox or nRF Connect. A 1KHz PWM is generated at pin 20 (led 4). Note that this is just a very quick prototype done in 10min, for an end-product you might want to create your own custom service for this.

Extract the .rar file in the ble_peripheral folder.

devzone.nordicsemi.com/.../ble_5F00_app_5F00_uart_5F00_pwm_5F00_driver_5F00_1KHz.rar

EDIT:

Here is the custom service tutorial + PWM Driver. Write to the custom characteristic to adjust the PWM duty cycle.

devzone.nordicsemi.com/.../ble_5F00_app_5F00_template_5F00_pwm_5F00_driver.rar

RE: Beginner needing help with basic structure and pwm

jmguk41 — Thu, 12 Apr 2018 13:39:09 GMT

Its in the right location. Not all files are missing. I spent most of the night adding include file locations, still have errors. I am out of time and in danger of losing the client.

If anyone offers code writing services, I am looking for someone to write a solution for me. I will come back to this later when I have time.

EDIT: So, after a windows update and reboot, all seems to be well and the project compiles perfectly.

Thank you guys for all your help. I still have a ton of questions - I have no idea how to receive a value from an app and use it to alter pwm duty cycle yet.

RE: Beginner needing help with basic structure and pwm

Bjørn Kvaale — Thu, 12 Apr 2018 08:01:37 GMT

Are you sure you have added the code at the right place in the folder structure? The compiler_abstraction.h file can be found in nRF5_SDK_15.0.0_a53641a\modules\nrfx\mdk\. If you open SES, right click on Project -> Edit Options -> change to Common Private Configuration -> Preprocessor -> User Include Directories, you can see the mdk folder at the bottom:

Go to the location of your segger folder & see if that is at the correct location. You might need to add an extra folder at the top of the folder structure to get the correct include directories. You could also change the include directories location, but then you would probably need to do this for multiple instances.

Basically, you want to make sure that the folder structure is identical to the other examples located in the SDK folder.

RE: Beginner needing help with basic structure and pwm

jmguk41 — Thu, 12 Apr 2018 02:13:06 GMT

Ok, downloaded Segger, changed the RAM locations per the tutorial, opened the tutorial SES project file, tried to build and there are many errors lol

Looks like the same issues before with missing files that the includes are looking for. First missing file is compiler_abstraction.h, which is stopping nrf_log_backend_serial.c and nrf_log_default_backends.c from compling.

RE: Beginner needing help with basic structure and pwm

Daniel Wang — Wed, 11 Apr 2018 20:38:12 GMT

Happy to help! I would recommend moving to Segger Embedded studio. You don’t wan't to spend the development phase working around the max code limit in Keil(free version, full version is expensive). SES is also completely free when using Nordic chips!

RE: Beginner needing help with basic structure and pwm

jmguk41 — Wed, 11 Apr 2018 20:31:42 GMT

YAY!! Thank you!

Now I'm back to exceeding the maximum number of bytes so I have to work with SES or GCC. Unless there is something I can remove from this template?

RE: Beginner needing help with basic structure and pwm

Daniel Wang — Wed, 11 Apr 2018 20:25:14 GMT

Try adding ble_cus.c to the Application folder for the project (right click on the folder, and then Add existing files to Group "Application"...)

RE: Beginner needing help with basic structure and pwm

jmguk41 — Wed, 11 Apr 2018 20:19:18 GMT

Kiel v5.06 update 5 (build 528)

RE: Beginner needing help with basic structure and pwm

Daniel Wang — Wed, 11 Apr 2018 20:06:53 GMT

You are using Keil or SES ?

RE: Beginner needing help with basic structure and pwm

jmguk41 — Wed, 11 Apr 2018 19:59:16 GMT

Yes it is. ble_cus.c (and.h) are located in the same place.

RE: Beginner needing help with basic structure and pwm

Daniel Wang — Wed, 11 Apr 2018 19:56:50 GMT

What folder is the ble_cus.c and ble_cus.h located in ?

Is the main.c file located like this:

sdk-folder\examples\ble_peripheral\custom_ble_service_example\main.c ?

What IDE/toolchain are you using?

RE: Beginner needing help with basic structure and pwm

jmguk41 — Wed, 11 Apr 2018 19:34:56 GMT

I did include ble_cus.h.

Additionally, I used the tutorial version of main.c and got the same error.

I am at the first compile stage.

I just tried using the example files in my project and get 2 errors:

.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol ble_cus_init (referred from main.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol ble_cus_on_ble_evt (referred from main.o).
Not enough information to list image symbols.
Not enough information to list load addresses in the image map.
Finished: 2 information, 0 warning and 2 error messages.
".\_build\nrf52832_xxaa.axf" - 2 Error(s), 0 Warning(s).

I tried compiling the example project and got lots of errors. Seems the include paths are wrong for many files, and some files are missing.

I noticed that in your example that ble_cus.c appears in a folder called nRF_Services but this is not created in my version.

This is so frustrating! 🙂 All I want to do is switch on and off an io pin and create a variable pwm signal! Arrggh.

RE: Beginner needing help with basic structure and pwm

Bjørn Kvaale — Wed, 11 Apr 2018 10:30:18 GMT

See this link for an explanation of what an implicit declaration is. Did you remember to include ble_cus.h in your main.c file (i.e. #include "ble_cus.h")? Which step have you reached in the tutorial when you get this error? I can recommend reading through the tutorial again & make sure you haven't missed a small line of code somewhere.

You can also compare your code with the solution code found here if that is easier (open the ble_cus.c, ble_cus.h and/or main.c files from the top of the tutorial link).

Also, regarding using Segger, I can highly recommend Segger Embedded Studio. Like mentioned above, it is free for Nordic SDK users (here is a youtube playlist for getting started). I cannot recommend using Eclipse unfortunately, as there are quite a few bugs. I have talked to a few customers & most of them complain that it takes a lot of time to get eclipse working. It is in my honest opinion easier to start with segger embedded studio.

RE: Beginner needing help with basic structure and pwm

jmguk41 — Tue, 10 Apr 2018 14:49:10 GMT

I'll definitely look in to GCC.

So right now I have fixed a few things but I cant get it to compile. The error code is:

..\..\..\main.c(380): warning: #223-D: function "ble_cus_init" declared implicitly
err_code = ble_cus_init(&m_cus, &cus_init);

This is the code the error is referring to:

static void services_init(void)
{
    /* YOUR_JOB: Add code to initialize the services used by the application.
       ret_code_t                         err_code;
       ble_xxs_init_t                     xxs_init;
       ble_yys_init_t                     yys_init;

// Initialize XXX Service.
memset(&xxs_init, 0, sizeof(xxs_init));

       xxs_init.evt_handler                = NULL;
       xxs_init.is_xxx_notify_supported    = true;
       xxs_init.ble_xx_initial_value.level = 100;

err_code = ble_bas_init(&m_xxs, &xxs_init);
APP_ERROR_CHECK(err_code);

       // Initialize YYY Service.
       memset(&yys_init, 0, sizeof(yys_init));
       yys_init.evt_handler                  = on_yys_evt;
       yys_init.ble_yy_initial_value.counter = 0;

       err_code = ble_yy_service_init(&yys_init, &yy_init);
       APP_ERROR_CHECK(err_code);
     */
   ret_code_t                         err_code;
   ble_cus_init_t                     cus_init;


   memset(&cus_init, 0, sizeof(cus_init));

   err_code = ble_cus_init(&m_cus, &cus_init);
   APP_ERROR_CHECK(err_code);

}

Its copied from the tutorial so I'm not sure what is going on.

RE: Beginner needing help with basic structure and pwm

davidlr — Mon, 09 Apr 2018 22:30:41 GMT

Keil is ARM privative, both IDE and compiler. Try using some GCC based environment, you can use the licensed by Nordic SEGGER which is free for you to use commercially, or any GCC flavour, pure Makefiles or Eclipse.

All examples are availaible as GCC projects, and Segger projects.

At the end you will be glad to start GCCing yourself, some Keil features are kinda dark.

RE: Beginner needing help with basic structure and pwm

jmguk41 — Mon, 09 Apr 2018 17:34:10 GMT

Thanks for the link. I did see that earlier and have been working my way through it however I am getting an error when trying to compile the code.

L6050U: The code size of this image (34532 bytes) exceeds the maximum allowed for this version of the linker.

Apparently I'm using MDK-Lite which I downloaded via a link in the SDK.

RE: Beginner needing help with basic structure and pwm

Bjørn Kvaale — Mon, 09 Apr 2018 11:56:54 GMT

Might be useful to start with this custom service tutorial.