Assembly Programming

1. COMPUTER ORGANIZATION
& ASSEMBLY LANGUAGE
LECTURE # 10
BY MUHAMMAD JAFER
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2. CENTERAL PROCESSING UNIT
• Register Set
• Athematic Logic Unit
• Control Unit
• Data path
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3. INSTRUCTION CYCLE
• Instruction Register
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4. DATA PATH
• Capable of performing certain operation on data
• Athematic Logic Unit
• External Busses & Internal Busses
• Both can have different design
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5. ONE-BUS ORGANIZATION
• Single Bus
• One instruction fetching per CPU cycle
• Simple & Cheapest
• Slow
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6. TWO-BUS ORGANIZATION
• two Bus
• Two instruction fetching per CPU cycle
• In-bus & Out-bus design
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7. THREE-BUS ORGANIZATION
• Three Bus
• Two In-bus & one Out-bus design
• More busses will have data transfer faster
• More complex hardware design
• Expensive
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8. INSTRUCTION CYCLE EXAMPLES
• MOV AL,5
• ADD AL,[003]
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9. COMPLEX INSTRUCTION CYCLE
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10. INTERRUPTS
• Mechanism by which other modules (e.g. I/O)
may interrupt normal sequence of processing
• Program
• e.g. overflow, division by zero
• Timer
• Generated by internal processor timer
• Used in pre-emptive multi-tasking
• I/O
• from I/O controller
• Hardware failure
• e.g. memory parity error
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11. IF INTERRUPTS
•Suspend execution of current program
•Save context
•Set PC to start address of interrupt
handler routine
•Process interrupt
•Restore context and continue interrupted
program
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12. IF INTERRUPTS
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13. IF INTERRUPTS
•Suspend execution of current program
•Save context
•Set PC to start address of interrupt
handler routine
•Process interrupt
•Restore context and continue interrupted
program
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14. PROGRAM TIMING
SHORT I/O WAIT
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15. PROGRAM TIMING
LONG I/O WAIT
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16. CONTROL UNIT
• Part of CPU
• Management of Computer Resources
• Control and Timing Signals
• Directs Flow of Data
• CU Types
• Mircoprogrammed
• Hardwire
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17. MICROPROGRAMMED
• Memory Units storing Control Signals
• Inaccessible Memory Units in RAM or ROM
• Control Word is microinstruction
• Microinstruction = 1/More Microoperations
• Sequence of microinstructions are microprograms
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18. HARDWIRED
• Fixed Logical Instructions
• Far more faster
• Not cheaper & Complex
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19. CHAPTER REVIEW
• Fundamentals of Computer Organization and
Architecture by Mostafa Abd-Al-Barr & Hesham
AlRewini
• Chapter # 5
• CPU Basics
• Register Set
• Datapath
• CPU Instruction Cycle
• Control Unit
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