Datasheet

1309
SAM3X / SAM3A [DATASHEET]
Atmel-11057C-ATARM-SAM3X-SAM3A-Datasheet_23-Mar-15
42. True Random Number Generator (TRNG)
42.1 Description
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_CTRL register), the generator provides one 32-bit value every 84 clock
cycles. Interrupt trng_int can be enabled through the TRNG_IER register (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 register (TRNG_ODATA).
The normal mode of operation checks that the status register flag equals 1 before reading the output data register
when a 32-bit random value is required by the software application.
Figure 42-1. TRNG Data Generation Sequence
42.2 Embedded Characteristics
 Passed NIST Special Publication 800-22 Tests Suite
 Passed Diehard Random Tests Suite
 Provides a 32-bit Random Number Every 84 Clock Cycles
84 clock cycles
84 clock cycles
84 clock cycles
Read TRNG_ISR
Read TRNG_ODATA
Read TRNG_ISR
Read TRNG_ODATA
clock
trng_int
trng_cr
enable