please check this code

[j hemangini]

I have written a code for serial transmission on hyperterminal that is given below.
--------------------------------------------
entity Tx is
Port ( clk : in STD_LOGIC;
TxD : out STD_LOGIC;
switch : in STD_LOGIC);
end Tx;

architecture Behavioral of Tx is
signal count8bit:std_logic:='1';
signal count:integer:=0;
signal Bit_Count:integer:=0;
signal Data_Byte:STD_LOGIC_VECTOR(9 downto 0):= "1010010011";
begin
process(clk)
begin
if clk'event and clk='1' then
count <= count+1;
if count = 5208 then
count <= 0;
TxD <= Data_Byte(0);
for i in 1 to 9 loop
Data_Byte(i-1) <= Data_Byte(i);
end loop;
Bit_Count <= Bit_Count + 1;
if Bit_Count = 10 then
Bit_Count <= 0;
Data_Byte <= "1010010011";
end if;
end if;
end if;
end if;

end process;
end Behavioral;
--------------------------------------------------------------------

Out of this 10 bit fixed format 1010010011, i have used first and last bit as start and stop bit .
Remaining 8 bit format '01001001' is binary code of 'I'. I am communicating on baud rate of 9600.
But issue is that, when i communicate hyperterminal with kit(spartan-3a starter kit)
it starts transmiting 'R' instead of 'I'.
Is there something wrong in this code .
If someone know then please tell me.
thank you.

 

[tlp71@hotmail.com]

whic frequency have your clk?

 

[j hemangini]

it is 50Mhz.

 

[ihearme]

Your clock and count calculations look ok.

How about your hyperterminal port settings?
I usually use
data bits = 8
parity = none
stop bits = 1
flow control = none

 

[j hemangini]

I am using the same configuration for port setting.

 

[childs]

apparently u r transmiting "01010010" which is "R" this is coresponding to the a "0" and first 7 bits of your "1010010011", pls check your counting statement again, you maight start transmitting at wrong count

 

[j hemangini]

I am unable to find any problem.