In this presentation we can learn the basic concept of Arm Programmer's Model and different registers and its functions.

1. MICROCONTROLLER BASED SYSTEM DESIGN
“ARM PROGRAMMER'S MODEL”
V. KALAIRAJAN M.E;
ASSISTANT PROFESSOR,
ELECTRICAL AND ELECTRONICS ENGINEERING,
KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY.
1KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

2. “ARM PROGRAMMER'S MODEL”
VIEWS:
 ARM PROGRAMER'S MODEL.
 ARM REGISTERS.
 THREE SPECIAL FUNCTION REGISTERS.
 THE CURRENT PROGRAM STATUS REGISTER (CPSR).
 CONCLUSION.
 REFERENCES.
2KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

3. “ARM PROGRAMMER'S MODEL”
ARM PROGRAMER'S MODEL
 ARM is a flexible programmer’s designed architecture with
different applications.
 Design is simple, optimum and economic.
 A processor's instruction set defines the operations that the
programmer can use to change the state of the system
incorporating the processor.
 This state usually comprises the values of the data items in the
processor's visible registers and the system's memory.
 Each instruction can be viewed as performing a defined
transformation from the state before the instruction is executed to
the state after it has completed.
3KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

4. “ARM PROGRAMMER'S MODEL”
ARM REGISTERS:
 ARM has 31 general purpose 32 bit registers.
 16 registers only visible register.
 16 registers are user mode registers.
 Other registers are used to speed up execution processing.
 16 registers are R0 to R15. In this three registers(R13,R14,R15)
are special purpose registers.
 These three registers used for only important functions in the
program.
4KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

5. “ARM PROGRAMMER'S MODEL”
5KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

6. “ARM PROGRAMMER'S MODEL”
THREE SPECIAL FUNCTION REGISTERS:
 Stack pointer.
 Link Register.
 Program counter.
STACK POINTER (R13):
 It is used to store the head of the stack in the current processor
mode.
LINK REGISTER(R14):
 It is used when the interrupt is used in program.
 It is used to return when subroutine calls occurred.
PROGRAM COUNTER(R15):
 It is used to store the address of next instruction to be execute.
6KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

7. “ARM PROGRAMMER'S MODEL”
THE CURRENT PROGRAM STATUS REGISTER (CPSR):
 CPSR is used to store the current status of ALU after execution of
operations.
 The CPSR is used in user-level programs to store the condition
code bits.
 These bits are used, for example, to record the result of a
comparison operation and to control whether or not a conditional
branch is taken.
7KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

8. “ARM PROGRAMMER'S MODEL”
N: NEGATIVE:
 The last ALU operation which changed the flags produced a
negative result (the top bit of the 32-bit result was a one).
Z: ZERO:
 The last ALU operation which changed the flags produced a zero
result (every bit of the 32-bit result was zero).
C: CARRY:
 The last ALU operation which changed the flags generated a
carry-out, either as a result of an arithmetic operation in the ALU
or from the shifter.
V: OVERFLOW:
 The last arithmetic ALU operation which changed the flags
generated an overflow into the sign bit.
8KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL

9. “ARM PROGRAMMER'S MODEL”
CONCLUSION:
 In this above presentation we can learn about basic concept of
ARM programmers model , ARM registers, special registers, and
purpose of CPSR clearly.
REFERENCES:
 Mazidi, M.A.,“PIC Microcontroller” Rollin Mckinlay, Danny
causey Printice Hall of India, 2007.
 Ravichandran,C., and Arulaalan,M., “Microcontroller Based
System Design”, Suchitra Publications, Ist edition,2016.
 Dr.Balamurugan.C.R., Periyaazhagar., “Microcontroller Based
System Design”, Megnus Publications, Ist edition,2016.
 Online wikipedia search.
9KONGUNADU COLLEGE OF ENGINERING AND TECHNOLOGY, TRICHY ARM PROGRAMER'S MODEL