#### fahim1

##### Member level 4

heres my code and i defined signal "inp" but its initial value depends on input and in simulation it didnt get its value,i defined it in another process as u can see its now commented but it still didnt work

Code:

```
LIBRARY ieee;
USE ieee.std_logic_1164.all;
USE ieee.std_logic_unsigned.all;
USE ieee.std_logic_arith.all;
entity serialm is
port(a,b : in std_logic_vector(3 downto 0);
clk : in std_logic;
out3 : out std_logic_vector(7 downto 0));
end serialm;
architecture serialm_arch of serialm is
signal sum : std_logic_vector(2 downto 0) := "000";
signal count :integer := 0;
signal outtemp : std_logic_vector(7 downto 0) := "00000000";
signal s1,s2,carry1,carry2,carry3,ena: std_logic := '0';
signal inp :std_logic_vector(7 downto 0) := b(3 downto 0) & "0000";
begin
--process(a,b)
--begin
--if (clk ='1' and clk'event) then
--inp <= b(3 downto 0) & "0000";
--ena <='1';
--end if;
--end process;
process(clk)
variable sum0,sum1,sum2,sum3 : std_logic := '0';
variable c0,c1,c2,c3 : std_logic := '0' ;
variable temp0,temp1,temp2,temp3 : std_logic_vector(1 downto 0) :="00";
--variable inp :std_logic_vector(7 downto 0)
--inp := b(3 downto 0) & "0000";
begin
--if (ena ='1') then
if (clk='1' and clk'event) then
if (count <9) then
temp0(0) := ( a(0) and inp(3) )xor c0 ;
temp0(1) := ( a(0) and inp(3) )and c0 ;
sum0 := temp0(0);
c0 := temp0(1);
temp1(0) := (a(1) and inp(2))xor c1 ;
temp1(1) := (a(1) and inp(2))and c1 ;
sum1 := temp1(0);
c1 := temp1(1);
temp2(0) := (a(2) and inp(1))xor c2 ;
temp2(1) := (a(2) and inp(1))and c2 ;
sum2 := temp2(0);
c2 := temp2(1);
temp3(0) := (a(3) and inp(0))xor c3 ;
temp3(1) := (a(3) and inp(0))and c3 ;
sum3 := temp3(0);
c3 := temp3(1);
s1 <= sum0 xor sum1;
carry1 <= sum0 and sum1;
s2 <= sum2 xor sum3;
carry2 <= sum2 and sum3;
sum(0) <= s1 xor s2;
carry3 <= s1 and s2;
sum(1) <= carry1 xor carry2 xor carry3;
sum(2) <= ((carry1 or carry2) and carry3) or (carry1 and carry2);
outtemp(count ) <= sum(0);
count <= count +1 ;
inp <= '0'& inp(7 downto 1);
elsif (count = 9 ) then
out3 <= outtemp(7 downto 0);
-- ena <= '0';
end if;
end if;
--end if;
end process;
end serialm_arch;
```