The TRNG9880T is the sample variant of the TRNG9880. It is produced in small quantities using simpler production means compared to the TRNG9880, which is currently not in production.
The software is the same, and all electrical, mechanical, and interface specifications are identical to the TRNG9880.
Each unit is subject to extensive testing. Read about the tests in
Testing of the TRNG9880.pdf. This document is subject to change.