gate-level vs rtl vs behavioral

i'm somewhat new to digital design. recently i came across the following terms

gate-level
register transfer level (rtl)
behavioral

it looks to me that these are the ways of doing digital design. however i was not clear about actual differences between them.

so the questions are
1) what are the differences between the gate-level, register transfer level and behavioral designs?
2) if i look at the source code, whether it is verilog or vhdl, how do i know what kind of design it is, gate-level, register transfer level or behavioral?

thanks

Hello cyboman,

I think that this tutorial might answer all that for you.

Also if you are serious about learning this stuff, I would advice you to get a book to get you up to speed quickly. The one I used for precisely that purpose is "A Verilog HDL Primer" by J. Bhasker.

Hope that helps.

hello cyboman,

think of , say, 4to1 multiplexer.
you can write the code in verilog or vhdl for the mux.

there are thre ways describing the mux in hdl.

imagine the blackbox model with input and outputs of mux alone.

-if you write the code as the mux consisting of 'gates' ,
then it is 'structural' model.

-if you write the 'boolean equation' or 'truth table ' of mux
then it is 'rtl' model .

-on the other hand , without worrying the above two ,
you can write it as, something like,

if(selects0,s1==00)
o/p=a;
....

this model is 'behaviour'
in 'behaviuoral model u dont worry about what is the logic
or boolean equationof the mux.. just input/output relationship.

write its 'behaviour' ,in a highlevel construct of 'if...' etc.

hope u get.

srizbf
30thapril2010

Actually Register transfer level means you are doing operation on blocks of **broken link removed** as opposed to on single bits.

You said you were new to digital logic. Here is a **broken link removed** with pretty much everything. And all the circuits there are interactive.

Good luck