In I/O Interface (Interrupt and DMA Mode), we have discussed the concept behind the Interrupt-initiated I/O. To summarize, when I/O devices are ready for I/O transfer, they generate an interrupt request signal to the computer. The CPU receives this signal, suspends the current instructions it is executing, and then moves forward to service that transfer request. But what if multiple devices generate interrupts simultaneously. In that case, we have a way to decide which interrupt is to be serviced first. In other words, we have to set a priority...