SYSC Come to the PASS workshop with your mock exam complete. During the workshop you can work with other students to review your work.

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1 It is most beneficial to you to write this mock midterm UNDER EXAM CONDITIONS. This means: Complete the midterm in hour(s). Work on your own. Keep your notes and textbook closed. Attempt every question. After the time limit, go back over your work with a different colour or on a separate piece of paper and try to do the questions you are unsure of. Record your ideas in the margins to remind yourself of what you were thinking when you take it up at PASS. The purpose of this mock exam is to give you practice answering questions in a timed setting and to help you to gauge which aspects of the course content you know well and which are in need of further development and review. Use this mock exam as a learning tool in preparing for the actual exam. Please note: Come to the PASS workshop with your mock exam complete. During the workshop you can work with other students to review your work. Often, there is not enough time to review the entire exam in the PASS workshop. Decide which questions you most want to review the Facilitator may ask students to vote on which questions they want to discuss in detail. Facilitators do not bring copies of the mock exam to the session. Please print out and complete the exam before you attend. Facilitators do not produce or distribute an answer key for mock exams. Facilitators help students to work together to compare and assess the answers they have. If you are not able to attend the PASS workshop, you can work alone or with others in the class. Good Luck writing the Mock Exam!! Dates and locations of mock exam take-up:

2 PART 1 1) Briefly describe what the system bus is. 2) Describe the difference between computer organization and computer architecture. 3) List the components of the Von Neuman model of the CPU and briefly explain each. 4) What does the.end directive do. 5) List two actions performed by the assembler during its second pass.

3 PART2: SYSC ) Consider the following code snippet, will the jump statement included be taken give the reason for your answer. I. MOV AX, 6789h CMP AX, 0 JG somelabel II. MOV AX, 0FEDCh CMP AX,0 JLE Label 2) Consider the following code snippet, what will be the value of Data when this is executed..org 1000h Data:.db 23 3) For a 16-bit source, where will the result of a MUL instruction be stored in a 80x86 processor.

4 PART 3: SAMPLE CODE: SYSC 2001 Below is a sample program that goes through an array of numbers and increases all the numbers by 1. The program also counts how many numbers in the array are equal to 6. The array is terminated with a value of zero. Fill in the empty lines with the appropritate lines of code.org 0000h array: ; start of the array.db 1.db 2.db 3.db 4.db 5.db 6.db 0 terminating character of array Start: ; program start ; FIX ME (load the address of the first element of the array) MOV CL, 0 ; Counter for how many sixes have been found in the array check_if_zero: ; FIX ME (load the next element of the array ) CMP AL, 0 ;compares the element loaded to 0 JE end_of_array ;checks if we are at the end of the array check_for_six: ;FIX ME (checks if the element is a six) loop1: JE found_a_six ; ;FIX ME (increase the value of the element by 1) MOV [BX], AL INC BX ;replaces the old value with the increased value of the element ; increases the address to point to the next element in the array

5 JMP check_if_zero ;continues stepping through the array end_of_array: ;FIX ME ( end of array has been reached end the program) found_a_six: ;FIX ME (increment the counter for sixes) JMP loop1 ; carry out the increase operation on the element Quit: HLT.END start PART 4: Number System 1) Compute the decimal equivalent of the following value, assuming it s in 2 s complement 0xF2. 2) Compute the binary representation of the following decimal value ) Given that the value of the label extra is known to be 000Ah. Fill in the following memory space with its appropriate content for this instruction set. First:.dw 56 extra:.db 8 mystring:.db Hello

6 Address Value A 000B 000C 000D 000E PART 5: ARITHMETIC 1. Compute the result of , give the result in binary and show and show the state of the flags after. CF = SF = OF = ZF =