Qsn: In a memory mapped input/output:

A. the CPU uses polling to watch the control bit constantly, looping to see if device is ready

B. the CPU writes one data byte to the data register and sets a bit in control register to show that a byte is available

C. the CPU receives an interrupt when the device is ready for the next byte

D. the CPU runs a user written code and does accordingly

Answer: Option (B)

Check Page Rank