Random number generator example

[Jerry Easley]

I'm looking for an example program for a random number generator on a nRF52840-DK.

I want to now what #include statements I need, what initialization functions I need to call, the function to retrieve a random number, and any modifications I need to make to any build files i need to make. 

[Vidar Berg]

Hello, 

You can use the random API subsystem (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/services/crypto/random/index.html) for this. To use the API, you simply include the <zephyr/random/rand32.h> header and add CONFIG_ENTROPY_GENERATOR=y to your prj.conf. 

Here is a minimal example I made based on the Zephyr 'Hello World' sample:

hello_world_rand.zip

Note: CRYPTOCELL — ARM TrustZone CryptoCell 310 is the default entropy source if your build target is 'nrf52840dk_nrf52840'.

Best regards,

Vidar

[Jerry Easley]

Hi Vidar,

Excellent! Thank you so much!

[mej7000]

This is exactly what I was looking for... But, I would like to limit the range of the random number generated to 0-100.  Such as:  random(min, max). Is that possible with Zephyr? I'm not seeing it.