The problem of interrupt

hello!

I am learning how to edit a component,but there are two errors that I cann't solve,can anyone suggest me?

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the code is:

library ieee;

use ieee.std_logic_1164.all;

use ieee.std_logic_unsigned.all;

use ieee.std_logic_arith.all;

entity inter is

port(clk: in std_logic;

reset_n: in std_logic;

chipselect: in std_logic;

address: in std_logic;

write_n: in std_logic;

writedata: in std_logic_vector(31 downto 0);

read_n: in std_logic;

readdata: out std_logic_vector(31 downto 0);

irq: out std_logic);

end inter;

architecture behave of inter is

signal status:std_logic_vector(31 downto 0);

signal control:std_logic_vector(31 downto 0);

signal counter:std_logic_vector(23 downto 0);

signal sign:std_logic;

begin

process(reset_n,chipselect,write_n,read_n,writedata)

begin

if(reset_n='0')then

status<=(others=>'0');

control<=(others=>'0');

sign<='0';

elsif(chipselect='0')then

if(write_n='0')then

case address is

when '0'=>status<=writedata;

when '1'=>control<=writedata;

end case;

end if;

if(read_n='0')then

case address is

when '0'=>readdata<=status;

when '1'=>readdata<=control;

end case;

end if;

end if;

end process;

process(clk,chipselect,write_n)

begin

if(clk'event and clk='1')then

if(chipselect='0' and write_n='1' and control(0)='1' and status(0)='0')then

counter<=counter+1;

if(counter>"111111111111111111110000")then

sign<='1';

status<="000000000000000000000001";

else

sign<='0';

end if;

end if;

end if;

end process;

irq<=sign;

end behave;

thank you very much!