AVR_ Microcontroller_Muhammad Ali_Mazidi_AVR_Lecture6_Fall2023

AVR Microcontroller Muhammad Ali Mazidi

1. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Arithmetic, Logic Instructions, and Arithmetic, Logic Instructions, and
ProgramsPrograms
Chapter 6Chapter 6
The AVR microcontroller
and embedded
systems
using assembly and c

2. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Arithmetic InstructionsArithmetic Instructions
•Addition of unsigned numbers:

3. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•ADC and addition of 16 bit numbers:

4. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

5. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Subtraction of unsigned numbers:
•In many microprocessor, there are two different instructions for subtraction: SUB and
SUBB (subtract with borrow).

6. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

7. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

8. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

9. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

10. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

11. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Multiplication of unsigned numbers:

12. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Division of unsigned numbers:
•AVR has no instruction for divide operation. We can write a program to perform
division by repeated subtraction.

13. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Signed Number Concepts and Arithmetic Signed Number Concepts and Arithmetic
OperationsOperations
•Concept of signed numbers in computers:
•In everyday life numbers are used that could be positive or negative. For example, a
temperature of 5 degree below zero can be represented a -5, and 20 degrees above
zero as +20.
•The most significant bit (MSB) is set aside for the sign (+ or -), while the rest of the bits
are used for the magnitude.
•Signed 8 bit operands:

14. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Negative numbers:

15. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

16. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

17. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Overflow problem in signed number operations:

18. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•When is the V flag set?

19. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•What is the difference between the N and S flags?

20. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Logic and Compare InstructionsLogic and Compare Instructions
•AND:

21. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

22. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•OR:

23. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

24. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

25. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

26. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

27. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

28. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

29. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

30. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

31. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

32. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

33. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Rotate and Shift Instruction and Data Rotate and Shift Instruction and Data
SerializationSerialization
•In many applications there is a need to perform a bitwise rotation of an operand.
•In the AVR the rotation instruction ROL and ROR are designed specifically for that
purpose.
•Rotating through the carry:

34. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

35. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

36. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

37. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

38. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•Shit Instructions:

39. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

40. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

41. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.

42. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
•SWAP Instruction:

43. www. Mi cro D igit al Ed. com
BIH E universit y
AVR Microcontroller and Embedded System Using Assembly and C
Mazidi, Naimi, and Naimi
© 2011 Pearson Higher Education,
Upper Saddle River, NJ 07458. • All Rights Reserved.
Questions and AnswersQuestions and Answers
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