Devices have 8-bit addresses

Devices are accessed using IN and OUT instructions

There can be a maximum of 256 input devices and 256 output devices

Arithmetic and logic operations can be directly performed with the I/O data.

absolute

immediate

indirect

Relative

Direct memory access

Vectoring the interrupt

System Interrupt

Cycle stealing

1

2

3

None of these

only if an interrupt service routine is being executed

only if a bit in the interrupt mask is made 0

only if interrupts have been enabled by an EI instruction

none of these