protected boolean canConnectRedstone(int r) {
        return canInputRedstone(r) || canOutputRedstone(r);
    }
Mapped inputs and outputs of the gate.
OOOO IIII
High nybble is output.
Low nybble is input
fabrication/src/main/java/mrtjp/projectred/fabrication/engine/gates/RedstoneGateTile.java