Study Guide
CMSC 313  Midterm Exam                          name________________________________
Closed book, no notes, calculators OK                   returned with your  key  _ _
Multiple choice - circle the letter that is your answer. Choose closest if not exact.
Short answer, print neat. Not case sensitive. Unreadable by me is wrong.
Answer all questions with exactly one choice (zero, two or more is automatically wrong)
All questions refer to this course, using  NASM assembler, gcc and gdb
Comments are ignored. Work very carefully!

Study guide, in no particular order:

Q1:    Convert xxx from decimal to binary
Q2:    Convert .xxx from decimal to binary
Q3:    Convert xxx from binary to decimal 
Q4:    Convert .xxx from binary to decimal
Q5:    Know the commands to compile=nasm, link=gcc and run=./convert  programs
Q6:    Know what “global” and “extern” are used for, e.g. “main” and “printf”
Q7:    Know the register names and number of bits
Q8:    Know that “push” decrements ‘esp’ and “pop” increments ‘esp’
Q9:    Know that the “.data” segment takes db, dw, dd (8, 16, 32-bit) values
Q10:   Know that the “.bss” segment takes  resb, resw, resd (8, 16, 32-bit) reserve
Q11:   Know the assembly line format  label: op  operands  ; comment
Q12:   Understand what instructions do  mov, cmp, jmp, je, jg, jl, jz, add, sub
Q13:   Know what registers are used by
       mul, imul input eax , memory or constsnt, output lower product eax, upper edx
Q14:   Know what registers are used by
       div, idiv  dividend upper in edx, lower in eax, quotient in eax, remainder in edx
Q15:   Know what registers are used by “loop”=ecx, “ret”=eip, “jmp”=eip,
       “shrd” shrd  edx,eax,7 moves lower 7 bits of eax into edx, not changing eax,
       “shld”  shld  edx,eax,7 moves upper 7 bits of eax into edx, not changing eax 
Q16:   Be able to write small fragments of “C” code in assembly language
       add two values, “if” statement, “loop” statement, function call statement,
       function entry, function return, function passing arguments,
       int arr[10];  int *p;   int n=4;    arr[i]=i;
Q17:   Be able to add, subtract, multiply small binary numbers (ok to convert to decimal)\
Q18:   Understand that a program may exit via “C”, the operating system or BIOS
Q19:   Know that the BIOS starts executing when the computer is turned on and then
       loads a program from some device.


Expect up to 35 questions.
Some short answer.
Some multiple choice.
Some true-false.