CIS
rick07
4b.rtf1
PART I:
For drawings, you may use your word-processing drawing tools, graphic applications, or scanned hand drawings and ins ert them in the main document . Show all of your work .
1. Chapter 4 – Exercises, pages 185-187: 2(a); 4(a-g); 6(a); 8.
#2) (a) Suppose the main memory of the Pep/8 were completely filled with unary instructions. How many instructions would it contain?
#4) Answer the following questions for the machine language instructions 8B00AC and F70BD3.
(a) What is the opcode in binary?
(b) What does the instruction do?
(c) What is the register-r field in binary?
(d) Which register does it specify?
(e) What is the addressing-aaa field in binary?
(f) Which addressing mode does it specify?
(g) What is the operand specifier in hexadecimal?
#6) Suppose Pep/8 contains the following four hexadecimal values:
A: 19AC
X: FE20
Mem[0A3F]: FF00
Mem[0A41]: 103D
If it has these values before each of the following statements executes, what are the four hexadecimal values after each statement executes?
(a) C90A3F
#8) Determine the output of the following Pep/8 machine-language program if the input is tab. The left column is the memory address of the first byte on the line:
0000 490010
0003 490011
0006 490012
0009 510011
000C 510010
000F 00
2. Chapter 4 – Problems, page 187: 15.
#15) Write a machine-language program to add the three numbers 2, –3, and 6 and output the sum on the output device. Write it in a format suitable for the loader and execute it on the Pep/8 simulator.
