SR Latch With Control input

This is a modification of NAND Set-Reset (S-R/RS) Latch, refer to my circuit "NAND Set-Reset (S-R/RS) Latch", two additional NAND gates were used so that the circuit now includes an ENABLE function. When enable input (C) is high the S and R input can control Q and NOTQ output just as in the circuit NAND Set-Reset (S-R/RS) Latch. When C is low S and R are inhibited from controlling the output of the latch, Q and NOTQ simply retain their previous states.