This is a fun lil first pass at a modified-consensus voting chip for .
It really ought to include dual-redundant signal paths but probably won't.
Achieving functional safety requires being tolerant of individual hardware failures. The simplest way to achieve this is redundancy -- e.g. running your control algorithm on multiple microcontrollers such that even if one of them fails the algorithm keeps running. Normally you might just "or" the outputs together; this chip is us playing at a slightly more complicated / customizable means of combining outputs from multiple processors.
Inputs and outputs are digital signals (booleans). The output is a boolean also. In the case of disagreement, an additional "default" / failsafe value is provided as an input that the system can fall back on.