Teaching UGC NET Mock Test Series 2025 (Paper 1 & 2) Computer Organization and Architecture I/O Interface Input-Output Processor
Normally user programs are prevented from handling I/O directly by I/O instructions in them. For CPUs having explicit I/O instructions, such I/O protection is ensured by having the I/O instructions privileged. In a CPU with memory mapped I/O, there is no explicit I/O instruction. Which one of the following is true for a CPU with memory mapped I/O?
1
I/O protection is ensured by operating system routines
2
I/O protection is ensured by a hardware trap
3
I/O protection is ensured during system configuration
4
I/O protection is not possible