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/** \addtogroup rtng_module Working with RTNG
* \ingroup peripherals_module
* The TRNG driver provides the interface to configure and use the TRNG
* peripheral.\n
*
* The True Random Number Generator (TRNG) passes the American NIST Special
* Publication 800-22 and Diehard Random Tests Suites. As soon as the TRNG is
* enabled (TRNG_Enable()), the generator provides one 32-bit value every 84
* clock cycles. Interrupt trng_int can be enabled through TRNG_EnableIt()
* (respectively disabled in TRNG_IDR).
* This interrupt is set when a new random value is available and is cleared
* when the status register is read (TRNG_SR register). The flag DATRDY of
* the status register (TRNG_ISR) is set when the random data is ready to be
* read out on the 32-bit output data through TRNG_GetRandData().
*
* For more accurate information, please look at the SHA section of the
* Datasheet.
*
* Related files :\n
* \ref trng.c\n
* \ref trng.h\n
*/
/*@{*/
/*@}*/
/**
* \file
*
* Implementation of True Random Number Generator (TRNG)
*
*/
/*----------------------------------------------------------------------------
* Headers
*----------------------------------------------------------------------------*/
#include "chip.h"
/*----------------------------------------------------------------------------
* Exported functions
*----------------------------------------------------------------------------*/
/**
* \brief Enables the TRNG to provide Random Values.
* \param key This key is to be written when the ENABLE bit is set.
*/
void TRNG_Enable(void)
{
TRNG->TRNG_CR = TRNG_CR_ENABLE | TRNG_CR_KEY_PASSWD;
}
/**
* \brief Disables the TRNG to provide Random Values.
* \param key This key is to be written when the DISABLE bit is set.
*/
void TRNG_Disable(void)
{
TRNG->TRNG_CR = TRNG_CR_KEY_PASSWD;
}
/**
* \brief Data Ready Interrupt enable.
*/
void TRNG_EnableIt(void)
{
TRNG->TRNG_IER = TRNG_IER_DATRDY;
}
/**
* \brief Data Ready Interrupt Disable.
*/
void TRNG_DisableIt(void)
{
TRNG->TRNG_IDR = TRNG_IDR_DATRDY;
}
/**
* \brief Get the current status register of the given TRNG peripheral.
* \return TRNG status register.
*/
uint32_t TRNG_GetStatus(void)
{
return TRNG->TRNG_ISR;
}
/**
* \brief Get the 32-bit Output Data from TRNG peripheral.
* \return TRNG output data.
*/
uint32_t TRNG_GetRandData(void)
{
return TRNG->TRNG_ODATA;
}