how to use adders,multipliers, in virtex2...

[vahidkh6222]

i wanna write a code for FIR filter, and i know the algorithm somehow... but i'm not sure of how to use the multipliers in this devise. should i use COREGENERATOR and make my costumized adder and then instantiate it 50 times for every MUL function i need? is there any other easier way?

also for shift register... is it true to write just this simple code:

if clk='1' and clk'event then
x[2]<= x[1];
x[3]<=x[2];
...
...
..
endif?!!!!!


how about the adder ?
is it true to write:

a <= b + C; ?!!!
or again use the COREGEN and instantiations?!!!



tnx in advance.

 

[EDALIST]

You Can Look At :

**broken link removed**

**broken link removed**

 

[vahidkh6222]

tnx but it does not answer my quest, i need the vhdl syntax to do multiplying...

 

[tkbits]

If you are using XST (included with ISE and Webpack) from Xilinx, the software manuals can be retrieved from

**broken link removed**

The most helpful manuals will probably be the sythesis (sim) and library (lib) manuals.

 

[seety1981]

Hi... here is the VHDL language...

for adder: sum<=a+b;

Multiplexer (4-bit) :
begin
process (sel,a,b)
begin
if (sel='0') then
y <=a;
else
y<=b;
end if;
end process;
end logic;


And i'm not sure for the shift register...but i know the VHDL language for shift and register....

Ok, good luck

Regards,
Siti

 

[mendozaulises]

You can define the adders and multipliers very simply, but you need to use the unsigned and arith libraries. If this is not urgent I will pass you some VHDL code defining a multiplier. I do use instantiation. I really don't know why you should need 50 multipliers, what order is your filter?