Describe tri-state devices

Question

Describe the tri-state devices and explain why they are necessary in a bus oriented system?

Answer 1

In multiplexed bus system, most of the devices are connected to a common bus. If two or more devices attempt to utilize the bus at similar time, then data will be lost. Therefore only one device should be allowed to use the bus at a time. One method is to connect the devices via tri-state devices, that when disabled will efficiently disconnect devices from bus.