NES CIC security chip functional recreation

Re: Reverse Engineering the CIC
Thanks to die shots provided by neviksti, I've identified and mapped out the logic cells in Tengen's "Rabbit" CIC clone.

Y=(A&B)|(C&D)

Y=A (buffer)

Y=~(A&B)

Y=~(A|B)

Y=(A^B)

Y=~(A&B&C)

Y=~A

Y=~A

FF with async set+clear

Y=A, Z=~A

FF with async reset

Y=~(A|B), Z=(~A)|B

latch

Y=~((A&B&C)|D)

Y=A (delay line?)

Y=A

Y=~(A^B)

latch with async clear

Y=~(A&B&C&D&E)

Y=~(A|B|C)

Y=~((A&B)|(C&D))

Back