Match List – I and List II:

	List I		List II
a.	Isolated I/O	i.	Same set of control signal for I/O and memory communication
b.	Memory mapped I/O	ii.	Separate instructions for I/O and memory communication
c.	I/O interface	iii.	Requires control signals to be transmitted between the communicating units
d.	Asynchronous data transfer	iv.	Resolve the differences in control computer and peripherals

 

Choose the correct option from those given below:

Isolated I/O:

In isolated I/O, devices are treated in a separate domain. There are separate instructions for I/O and memory communication. Device register size is 8 bit in case of isolated I/O. In this, common bus for I/O and memory but separate for read and write control lines for I/O.

Memory mapped I/O: 

In this, same set of control signal for I/O and memory communication. Every bus is common due to which same set of instructions work for memory and I/O. In this, I/O devices are treated as a part of memory only.

I/O interface:

It resolves the differences in control computer and peripherals. It provides a method for transferring information between internal storage and external I/O devices.

Asynchronous data transfer:

It is when internal timing in each unit is independent from other and when registers in interface and registers of CPU uses its own private clock. It requires control signals to be transmitted between the communicating units.