Initialisation in Blinky example

RE: Initialisation in Blinky example

Jared — Tue, 23 Jun 2020 11:29:40 GMT

The MSP is initialized in the startup files of the project. See arm_startup_nrf52840.s and gcc_startup_nrf52.s files at SDK_ROOT\modules\nrfx\mdk

[quote user="Himanshu"]I assume that the other features (NFC, I2S SPI) are left to default power up state(please confirm) but what about the stack pointer[/quote]

Yes, they will not be activated unless requested explicitly.

regards

Jared

RE: Initialisation in Blinky example

Himanshu — Tue, 23 Jun 2020 11:11:34 GMT

My assumption is based on my previous experience with microcontroller.

When the controller is reset, the first instruction is to initialise stack pointer, pointing to the intended area of the RAM.

I assume that the other features (NFC, I2S SPI) are left to default power up state(please confirm) but what about the stack pointer

RE: Initialisation in Blinky example

Jared — Tue, 23 Jun 2020 07:22:06 GMT

"Blinky without Softdevice" indicates that you're using a project that doesn't use BLE. So exactly which stack initialization are you expecting? Also, what features? The peripherals of the nRF?

[quote user="Himanshu"][/quote]

The function

bsp_board_init(BSP_INIT_LEDS);

initialises the pin out for LED. I had assumed that there would be more on initialisation.

Why are you assuming that?

RE: Initialisation in Blinky example

Himanshu — Mon, 22 Jun 2020 16:52:41 GMT

@Jared

Many thanks for your response

I have already downloaded SDK (the full folder name on my computer is nRF5SDK160098a08e2). I have followed the suggestion on infocenter and I am using the Blinky without Softdevice (from the blank folder).

I go back to my original question. The Blinky project was ‘build and run’; this downloaded the program (hex file) into the kit. I could see the LED working.

I wish to find out the various initialisation; this includes stack initialisation, initialisation of various features of the nRF52840 chipset.

The function

bsp_board_init(BSP_INIT_LEDS);

initialises the pin out for LED. I had assumed that there would be more on initialisation.

RE: Initialisation in Blinky example

Jared — Mon, 22 Jun 2020 14:10:23 GMT

Hi,

This is good start for a understanding on how to make your own BLE project.

I also suggest that you download the Software Development Kit which contains several examples on how to use the peripherals on the nRF and several BLE example projects.

There are several blinky examples in the SDK, it seems that you're referring to the SDK example that doesn't use the Softdevice. ble_app_blinky is a blinky example that has BLE.

Documentation on the nRF52840, the SDK libraries and more can be found at infocenter.

Good luck with your projects 🙂

regards

Jared