SLAU962A December 2025 – June 2026 MSPM33C321A , MSPM33C321A-Q1
In the event that the run-time health test identifies that insufficient entropy can be present, the health fail (IRQ_HEALTH_FAIL) interrupt is asserted and the TRNG state machine enters the ERROR state. Due to the random nature of the TRNG module, it is possible for a health failure to be indicated in some cases even when the TRNG is working properly. To determine if there is a true loss of entropy, the following procedure is recommended:
The TRNG does provide diagnostic information to indicate which test(s) failed. To determine which runtime test(s) are failing, check the REP_FAIL and ADAP_FAIL bits in the STAT register for the repetition test and adaptive proportion test, respectively.