SLAU847D October 2022 – May 2024 MSPM0L1105 , MSPM0L1106 , MSPM0L1227 , MSPM0L1228 , MSPM0L1228-Q1 , MSPM0L1303 , MSPM0L1304 , MSPM0L1304-Q1 , MSPM0L1305 , MSPM0L1305-Q1 , MSPM0L1306 , MSPM0L1306-Q1 , MSPM0L1343 , MSPM0L1344 , MSPM0L1345 , MSPM0L1346 , MSPM0L2227 , MSPM0L2228 , MSPM0L2228-Q1
The digital startup health test is run by application software when powering up the TRNG module. This built-in self-test verifies that the digital block is functioning properly by running predefined sequences of digital samples through the complete digital block while checking for expected outputs. The test sequence includes eight tests. Each test requires 1024 TRNG clock cycles to complete, as 1024 samples are input to the digital block for each test.
The results of the digital startup self-test are reported in the DIG_TEST field of the TEST_RESULTS register. Each test reports its status in an individual result bit. As each test passes, the corresponding bit in DIG_TEST is set by hardware. Upon completion of the digital start up self test, a pass condition is indicated if all eight bits in the DIG_TEST field of the TEST_RESULTS register are set. If any bit in the DIG_TEST field is not set, this indicates a failing test. The TRNG is not usable if any of the digital startup health tests fail.