7. What are tri-state devices and why they are
essential in a bus oriented system?
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Answer / santosh v pai
A device which has one input,one enable and one output line
is called tri-state device,if two different devices wants a
common bus then tri-state device are essential to assign bus
to any one of them in bus orientation system.
| Is This Answer Correct ? | 170 Yes | 27 No |
Answer / debarun kar
In a multiplexed bus system, many devices are connected to
a common bus. If 2 or more devices attempt to use the bus
at the same time , then data will be lost. Thus only one
one device must be allowed to use the bus at a time. O e
method is to connect the devices through tri-state
devices , which when disabled will effectively discoonect
devices from the bus.
| Is This Answer Correct ? | 128 Yes | 24 No |
Answer / arjun
Tristate also prevents loading effects caused by devices
connected on to the bus...
(adding to what has been written above)
| Is This Answer Correct ? | 43 Yes | 12 No |
Answer / swap
A tri-state device is normally a digital device. It means the device is in the high state, the low state, or in a high impedance state to prevent loading. The high and low states may have a fairly low impedance, anywhere from just a few ohms to 10 k ohms. The high impedance state would be in the megohms. An analog device would probably be either on or high state. There wouldn't be any real high or low states for analog as the output is continuously variable from 2 set limits.
The sites below have good information.
| Is This Answer Correct ? | 34 Yes | 12 No |
Answer / prasad
Tri state buffer is nothing but three state buffer . Two states are equivalent which is logic 0 or 1 . Third state is high impedance state . It behaves like open circuit. Third state is nothing but control input ,when control input is high (1) whatever we are giving input same we are getting as output . When control input is low(0) .the output goes to high impedance state (either 0 or 1) .
| Is This Answer Correct ? | 1 Yes | 4 No |
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