1.2.26 1.4.27 1.6.26 1.9.24 1.32.30 1.38.26 1.39.22 1.40.25 True Random Number Generator (TRNG)

As soon as the TRNG is enabled, the module provides a new 32-bit random data, for every 84 peripheral clock cycles.

The TRNG can optionally generate an interrupt when a new random value is available.

Using The Library

The library provides both blocking and callback methods to generate and read the random number.

  • With blocking API, it enables the TRNG module, waits for new random number to be available and then returns the newly generated random number.

  • With callback, it enables the TRNG module and the registered callback function will be called once the new random value is available.

Blocking API

The example code to generate 32-bit random number using blocking API is given below.

uint32_t trueRandomNumber

trueRandomNumber = TRNG_ReadData();

Callback method

This example demonstrates how to use callback to generate 32-bit random number.

uint32_t trueRandomNumber;

/* Random number is provided as part of callback */
void TRNG_EventHandler(uint32_t randomNumber, uintptr_t context)
{
    trueRandomNumber = randomNumber;
}

int main(void)
{
    /* Register Callback */
    TRNG_CallbackRegister(TRNG_EventHandler, (uintptr_t) NULL);

    /* Enable TRNG */
    TRNG_RandomNumberGenerate();
}

Library Interface

True Random Number Generator peripheral library provides the following interfaces:

Functions

Name Description
TRNG_Initialize Initializes TRNG module of the device
TRNG_RandomNumberGenerate Initiates generation of random number using the TRNG peripheral in interrupt mode
TRNG_ReadData Generates and returns a 32-bit random number in blocking mode
TRNG_CallbackRegister Sets the pointer to the function (and it's context) to be called when the random number is ready to be read

Data types and constants

Name Type Description
TRNG_CALLBACK Typedef Defines the data type and function signature for the TRNG peripheral callback function