DW,
I would post, but, as I noted above, I got a dire warning last time about revealing stuff not already in the public domain.
However, as a guide, the inputs are all duplicated and cross-checked, there are performance models of the engine and the FMV and the expected outputs are compared with the actual outputs, there are reversion modes should there be a loss of a speed, temperature or pressure input (the GE scenario of freezing probes is unlikely to fool the R-R FADEC), the FADEC hardware is continually checked for correect function etc, etc.
The whole lot is validated to be what is wanted and verified for function, starting with the lowest assembler and finishing with a full-up systems rig test.
I have faith in the product, I have flown on 777s since the incident without qualms!
VnV...