The document discusses basic concepts of computer architecture, focusing on register organization and stack organization. It explains the two types of registers: special purpose and general purpose, as well as the operations of a stack (push and pop). Furthermore, it highlights the application of stack organization in evaluating arithmetic expressions using reverse Polish notation.

1. CLASS PRESENTATION
UNIT-1
Mohammad Asif Iqbal
Assistant Professor,
Deptt of ECE,
JETGI, Barabanki

2. CLASS TEST

3. Q1:-HOW CAN YOU DROP A RAW
EGG ONTO A CONCRETE SURFACE
WITHOUT CRACKING IT.

4. WHAT WE WILL STUDY IN THIS CLASS….
1 General Register Organization
2 Stack Organization

5. General Register
Organization

6. REGISTERS
Small units of memory to hold
data/instructions temporally
during execution.
There are 2 kind of register in
the CPU.
1. Special purpose register
2. General purpose register

7. SPECIAL PURPOSE REGISTER
These are used for the specific purpose by the control
hardware
PROGRAM CONTROL (PC): used to remember the location
in memory of the instructions currently being executed.
INSTRUCTION REGISTER (IR): Used to remember that
instruction.
PROCESSOR STATUS REGISTER: used to remember status
information about current state of processor, e.g. whether
an arithmetic overflow has occurred.

8. GENERAL PURPOSE REGISTER
Available for use by the programmer
Useful for remembering the useful data
Why is it a good idea to do this?

9. WHY USE GENERAL PURPOSE REGISTERS?
There is a large speed disparity between the processor and the
memory where instructions and data are stored
Consider a 1 GHz processor
oThis frequency corresponds to a 1 nanosecond time scale.
oMilli (10-3), micro (10-6) nano (10-9)
oG (giga) 230 for memory ; 109 for frequency, disk size.
Memory : 100 nanosecond time scale
Aside: More on nanosecond
ospeed of light: 300,000km/sec or 0.3 m/nsec

10. GENERAL PURPOSE REGISTER
Available for use by the programmer
Useful for remembering the useful data
A typical processor today has 32 GPRs, say R0, R1,….R31
The operands to an instruction could come either from
registers or from main memory.

11. Stack
Organization
PART TWO

12. STACK ORGANIZATION
Stack or LIFO(Last-In, First-Out)
oA storage device that stores information
•The item stored last is the first item retrieved = a stack of tray
oStack Pointer (SP)
•The register that holds the address for the stack
•SP always points at the top item in the stack
oTwo Operations of a stack : Insertion and Deletion of Items
•PUSH : Push-Down = Insertion
•POP : Pop-Up = Deletion

13. TYPES OF STACK
1) Register Stack (Stack Depth: LIMITED)
oA finite number of memory words or
register(stand alone)
2) Memory Stack (Stack Depth: FLEXIBLE)
oA portion of a large memory

14. REGISTER STACK
0
)1()0(
][
1




EMTY
FULLthenSPIf
DRSPM
SPSP Increment SP
: Write to the stack
: Check if stack is full
: Mark not empty
Push Operation
The first item is stored at address 1, and the last item is stored at address 0
Pop Operation
0
)1()0(
1
][




FULL
EMTYthenSPIf
SPSP
SPMDR : Read item from the of stack
: Decrement Stack Pointer
: Check if stack is empty
: Mark not full

15. EXAMPLE OF PUSH& POP OPERATION.
D
A
00
10
DR
FULL EMTY PUSH A
01
PUSH B
10
PUSH C
11
1 0
FULL EMTY
PUSH D
POP D
D
DR

16. MEMORY STACK
Push Operation
The first item is stored at address 4000
Pop Operation
DRSPM
SPSP


][
1
1
][


SPSP
SPMDR
Program
(instructions)
Data
(operands)
Stack
SP
PC
AR
DR
1000
2000
4001
3000
4000
3999
3998
3997
Address
Memory unit
Start Here

17. RPN (Reverse Polish Notation)
The common mathematical method of writing arithmetic
expressions imposes difficulties when evaluated by a
computer
A stack organization is very effective for evaluating
arithmetic expressions
A * B + C * D  AB * CD * +
( 3 * 4 ) + ( 5 * 6 )  34 * 56 * +
3 12
6
5
42
30
12
5
1212
4
3
43 +*65*

18. HERE IS YOUR ANSWER….
ANY WAY YOU WANT, BECAUSE A
CONCRETE FLOOR IS VARY HARD TO
CRACK.

19. THANK YOU!