This document discusses direct and indirect branch instructions in computer system architecture. Direct branch instructions change the program counter (PC) directly to a new address, while indirect branch instructions first load the address from memory into the address register (AR) and then change the PC to that address. Examples are provided of before and after memory contents and register values for both direct and indirect branch instructions.

1. Computer system architecture
BY: DRISHTI BHALLA
BTECH CSE
1838

2. BUN INSTRUCTION
1. Direct
2. Indirect

3. • BUN
• Opcode =8
PC <- AR
• BUN_I
• Opcode =9
AR <- Main[AR]
PC <- AR

4. BEFORE
EXECUTION…
DIRECT :
AC=A937
PC=022
Main[AR]=082

6. AFTER EXECUTION…

8. BEFORE EXECUTION…
INDIRECT :
AC=A937
PC=022
Main[AR]=298
Main[298]=B8F2

10. AFTER EXECUTION…

12. THANK YOU !!!!