Test 2 CMSC 2100 Fall 2025

Name ______________________________________

• Please answer each question fully, carefully and thoughtfully.
• No credit will be given for unreadable answers, please write neatly.
• Please answer on the paper provided. Use as much paper as you wish.
• Answer the questions in any order, but please number each answer.
• Put your name on the top of this page and staple it to your answers.

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  1. For the expression F = Σ m(1,3,8,10,12,14)
     1. [5 points] Simplify using the Karnaugh maps as discussed in class.
     2. [5 points] Simplify using the Quine-McCluskey method as discussed in class.
     
     
  2. Multiplexers
     1. [2 points] Describe the input and output of a multiplexer.
     2. [2 points] Describe the relationship in size between the input and the control lines.
     3. [3 points] What problem does a multiplexer solve in circuit design?
     4. [3 points] Implement a multiplexer using and/or/not gates.
     
     
  3. Basic Memory
     1. [3 points] What is the difference between a flip-flop and a latch?
     2. [3 points] Describe the operation of the D flip-flop
     3. [4 points] Build a three bit register out of D flip-flops
     
     
  4. Larger Memory
     1. [4 points] Describe the typical control lines for a RAM.
     2. [2 points] Describe the operations supported by RAM using the control lines described above.
     3. [4 points] How can a 16x4 RAM chip be used to implement a 16x8 memory? Draw a simple diagram.
     
     
  5. Fetch-Decode-Execute
     1. [2 points] Describe the fetch-decode-execute algorithm/cycle
     2. [3 points] Describe the role of registers in this algorithm, include register names.
     3. [5 points] How can the decode/execution portions of fetch-decode-execute cyccle be implemented using a ROM?