22. _________ is a single control line that informs destination unit that a valid is available on the bus ?
A.Ping
B.Token
C.Handshake
D.Strobe

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23. Which technique has one or more control signal for acknowledgment that is used for intimation ?
A.Ftp
B.Ping
C.Strobe
D.Handshaking

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24. A keyboard has which type of asynchronous transfer mode ?
A.Serial
B.Parallel
C.Optimal
D.Joint

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25. Which technique helps processor to run a program concurrently with input output operations ?
A.IOP
B.DMA
C.Interrupt driven I/O
D.DCA

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26. Which exception is also known software interrupt ?
A.Trap
B.Call
C.System Call
D.All of above

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27. User programs interact with I/O devices through ?
A.Operating System
B.Hardware
C.Buses
D.Processor

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28. Which table handle store address of interrupt handling subroutine ?
A.Vector table
B.Symbol link table
C.Interrupt vector table
D.None of above

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