wanted solution for this problem

[RVSachin]

Hi everyone,

If data_in 'n'bits wide and data_out = k*n wide where k is a positive integer then if for a particular case data_in = 4 bits and k = 4,and data_in is changing arbitarily as A, B, C, D, I want data_out as "A000", "AB00" "ABC0", ABCD" at each rising edge of clock.
i.e, at every k th + ve edge of clk, the data is combined into one single word of data_out width.

This should be valid for parameterised data_in width and any value of k.

Can some one please help in this regard.

 

[Guest_imported]

I dont have time to write the code but i can give a qualitative answer. See if that helps.

You need a counter which counts from 0 to 3 and goes back to 0.

When counter is 0 => load data_in into first slot (of n bits) and zero out the rest of the 4 slots. You will get "A000"

when counter is 1 => load data_in into second slot but feedback old data into first slot

and so on when counter is 2 and 3.

the main logic will look something like this

case count is
when 0 =>
data_out (15 downto 12) <= data_in;
data_out (12 downto 8) <= &quot;0000&quot;;
data_out (7 downto 4) <= &quot;0000&quot;;
data_out (3 downto 0) <= &quot;0000&quot;;

when 1 =>
data_out (15 downto 12) <= data_out(15 downto 12);
data_out (12 downto 8) <= data_in;
data_out (7 downto 4) <= &quot;0000&quot;;
data_out (3 downto 0) <= &quot;0000&quot;;

when 2 =>
data_out (15 downto 12) <= data_out(15 downto 12);
data_out (12 downto 8) <= data_out (12 downto 8);
data_out (7 downto 4) <= data_in;
data_out (3 downto 0) <= &quot;0000&quot;;

similarly whe count is 3