Conacatenation 에서 비트를 묶는다는게
(reset)
r_vaild=0,0,0, i_vaild=0
(posedge clk)
r_vaild[1:0]=0,0 + i_vaild=1 -> r_vaild=[0,0,1] o_vaild=r_vaild[2]=0
(posedge clk)
r_vaild[1:0]=0,1 + i_vaild=1 -> r_vaild=[0,1,1] o_vaild=r_vaild[2]=0
(posedge clk)
r_vaild[1:0]=1,1 + i_vaild=1 -> r_vaild=[1,1,1] o_vaild=r_vaild[2]=1
. . .
요런 연산을 하는건가요..?