The DSi's product.log log tell us exactly what went on the in factory from the start of a DSi's life. The screenshot here is a log viewer from TWL EVA.
We can see the names of the specific tests run (TP_CAL, AGING, FINAL), what they were used for (the L in version means LINE), and when they were run.
We can see the names of the specific tests run (TP_CAL, AGING, FINAL), what they were used for (the L in version means LINE), and when they were run.