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2. 118] Suppose you have been hired by Three Mile Island (TMI) to help maintain software and hardware There is currently a problem. One system

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2. 118] Suppose you have been hired by Three Mile Island (TMI) to help maintain software and hardware There is currently a problem. One system requires a user to swipe a card with a magnetic ID numbe and then enter a PIN. But the system isn't allowing users to log in. After running several cards through and dumping the contents of memory, you narrow the problem down to either the chip that reads the User ID number off of the card, the chip that reads the PIN, or the chip that accepts the ID number and PIN and matches them to entries in a database. The program code for each operation resides on different chips. The ID number reader chip (let's callt Chip 1) reads in the ID number (an unsigned decimal number) and stores it in memory (in binary of course). The PIN reader chip (let's call it Chip 2), accepts a PIN (as ASCII text) and stores it in memory (again, as a string of Os and 1s). Chip 3 contains the code that compares the ID number and resides on different chips. The ID number reader chip (let's callt Page 1 o htps turing cs.hbg.psu.edu/cmpsc 312/hw2.htm 312 2/4/19, 12 57 PM PIN to a database entry to either allow or deny access to the system. s a computer scientist, you know how to look at the contents of memory. The debugger you are using of zeros and ones). displays the contents of memory to you as hexadecimal digits (so you don't have to look at a sequence TMI has given you a demo user ID card, with an ID number (in unsigned decimal) and PIN (in ASCI). The card's ID number is 3133078222, and the PIN is NUKE, The ID# and PIN are valid and matching entries exist in the database. In fact, they have cleared the database and your test card and PIN are the ONLY ones that should be allowed while you are debugging the problem (this will make searching the database much faster). You know the database entry itself is correct. The idea is that you can swipe the card, then enter the pin, and then immediately check the contents of memory. The goal is to determine if the error is occurring on Chip 1, Chip 2, Chip 3 (or any combination of these). You can determine this by comparing what you see in memory to what you know was input into the program for each chip and whether or not you get access. Below are some possible sets of results. The first number is the hexadecimal number in memory representing the ID number read in by Chip 1. The second number is the hexadecimal number representing the PIN that was read in and stored by Chip 2. The third value represents whether access was allowed or denied as determined by Chip 3. In each case (these are SEPARATE cases), specify on which chip(s) the error(s) occur(s). (There may be more than one error; if so, you should least list them all.) a. BABEFACE, 4E554B45, access denied b. BABEFAC1, 4E554B45, access allowed C. BABEFACE, 4E544445, access denied d. BABEPAC1, 4E554B45, access denied e. BABEFAC1, 4E554A45, access denied f. BABEFAC1, 4E544445, access allowed

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