This project will combine the microcontroller and memory management topics that we have discussed this semester to explore secure programming practices in the context of embedded systems. It involves a simplified implementation of a security system. This system is written to accept input from a $16-$key keypad matrix, connected to one of the BIG$8051\text{'}$s I$/$O ports. The firmware for this system deliberately exhibits several poor programming practices; in particular, it contains a nasty vulnerability which will allow anyone who understands it to "open the door," even if they do not know any of the correct door codes! Your first task will be to discover the nature of the vulnerability, and a minimal and consistent method of exploiting it$.$

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