tri-state vs muxes .which is better for data buses?

tri-state vs muxes

Tr-state or Mux logic...which is better for data buses?? Why?

tri-state vs muxes

I cannot say I know what you're asking for because mux and tristate is two different things.
Tristate alows you to send and recieve data on same bus while Mux/demux alows you to reduce number of bus wires to send same amount of data. No reason why they cannot be combined.

Also you forgot to mention parallell in series out register which may be an alternative to a mux.

Re: tri-state vs muxes

From a set of sub-bus lines one can drive a DATA BUS...........

1) We can place tri-state buffer in sub-bus lines (based on control signals)
2) The sub-bus lines can be selected using a mux to drice DATA BUS (control signals as selction lines)

Re: tri-state vs muxes

The only situation where I can think of this would really matter is when you have a large databus. See example below:


---------- 64
| |<--/----
64 | mux | 64
<---/---- | |<--/----
| | 64
| |<--/----
| | 64
| |<--/-----
----------

A mux is used to select one of the 4 input data. This would require a large mux. When synthesize, this large mux would probably be synthesize into several levels of smaller muxes, and as a result, increases the delay of the data and make it harder to meet timing.

If you change the above design to use tri-state buffers, like below, then it's easier to meet timing.
64
<-----/---tri-state-----
64
64 <-----/---tri-state-----
<----/----- 64
<-----/---tri-state-----
64
<-----/---tri-state-----


- Hung

tri-state vs muxes

skyfaye

It might be a god idea to draw the diagram using propriate software. Using Inkscape you can get very nice drawings. Paint (shipped with windows) can also be used to draw simple drawings, even if the result won't be as fine as for Inkscape.

Point is (might be this forum only) that text drawings doesn't work as intended. I tried to copy your drawing and aplying code tags around graphic. Even that was not successfull because it seems that width of space character in text editor differ from space when viewed in forum, even if it's closed by code tags.

[edit]
I took my time to draw it in Inkscape.

tri-state vs muxes

It is also possible to wrap your textual drawings in the [ code ] [ /code ] (no spaces) tags to preserve format.