help needed on 16 bit risc processor in VHDl

hello guys can i get complte code for a 16 bit risc processor written
in VHDL, i have developed code for it but im not sure whether it is
correct can any one correct my code


-HEADER FILE INTILISATION
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

--ALU INPUT DECLARATION

entity pro is
port(a,b:in std_logic_vector(7 downto 0);
s: in std_logic_vector(3 downto 0);
y: out std_logic_vector(9 downto 0)
);
end pro;

--ALU ARCHITECHURE MODULE

architecture project of pro is
signal temp:std_logic_vector(9 downto 0);
begin
process(a,b,s)
begin
--ACCORDING TO CONTROL SIGNAL
--ARTHMATIC OR LOGICAL FUNCTION SELECTION
case s is
when "0000"
=> temp<=a+b;
when "0001"
=> temp<=a-b;
when "0010"
=> temp<=a*b;
when "0100"
=> temp<=a and b;
when "0101"
=> temp<=a or b;
when others
=>temp<=a xor b;

end case ;

end process;
--PRINT OUTPUT
y<=temp;
end project;


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library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;



entity CPU is
port (
PADDR : out std_logic_vector(31 downto 0);
PDATA : in std_logic_vector(15 downto 0);
O_PRAM_DOUT : out std_logic_vector(15 downto 0);
PORTA_IN : in std_logic_vector(7 downto 0);
PORTA_OUT : out std_logic_vector(7 downto 0);
PORTA_OE_L : out std_logic_vector(7 downto 0);

PORTB_IN : in std_logic_vector(7 downto 0);
PORTB_OUT : out std_logic_vector(7 downto 0);
PORTB_OE_L : out std_logic_vector(7 downto 0);

PORTC_IN : in std_logic_vector(7 downto 0);
PORTC_OUT : out std_logic_vector(7 downto 0);
PORTC_OE_L : out std_logic_vector(7 downto 0);

PORTD_IN : in std_logic_vector(7 downto 0);
PORTD_OUT : out std_logic_vector(7 downto 0);
PORTD_OE_L : out std_logic_vector(7 downto 0);

DEBUG_W : out std_logic_vector(7 downto 0);
DEBUG_PC : out std_logic_vector(10 downto 0);
DEBUG_INST : out std_logic_vector(15 downto 0);
DEBUG_STATUS : out std_logic_vector(7 downto 0);

RESET : in std_logic;
CLK : in std_logic
);
end;

architecture RTL of CPU is

-- component definitions

component IDEC is
port (
INST : in std_logic_vector(11 downto 0);

ALU_ASEL : out std_logic_vector(1 downto 0);
ALU_BSEL : out std_logic_vector(1 downto 0);
ALU_ADDSUB : out std_logic_vector(1 downto 0);
ALU_BIT : out std_logic_vector(1 downto 0);
ALU_SEL : out std_logic_vector(1 downto 0);

WWE_OP : out std_logic;
FWE_OP : out std_logic;

ZWE : out std_logic;
DCWE : out std_logic;
CWE : out std_logic;
BDPOL : out std_logic;
OPTION : out std_logic;
TRIS : out std_logic
);
end component;

component ALU is
port (
ADDSUB : in std_logic_vector(1 downto 0);
BIT : in std_logic_vector(1 downto 0);
SEL : in std_logic_vector(1 downto 0);

A : in std_logic_vector(7 downto 0);
B : in std_logic_vector(7 downto 0);
Y : out std_logic_vector(7 downto 0);
CIN : in std_logic;
COUT : out std_logic;
DCOUT : out std_logic;
ZOUT : out std_logic
);
end component;

component REGS is
port (
WE : in std_logic;
RE : in std_logic;
BANK : in std_logic_vector(1 downto 0);
LOCATION : in std_logic_vector(4 downto 0);
DIN : in std_logic_vector(7 downto 0);
DOUT : out std_logic_vector(7 downto 0);
RESET : in std_logic;
CLK : in std_logic
);
end component;

-- type/constant definitions
constant STATUS_RESET_VALUE : std_logic_vector(7 downto 0) := x"18";
constant OPTION_RESET_VALUE : std_logic_vector(7 downto 0) := x"3F";
constant INDF_ADDR : std_logic_vector(2 downto 0) := "000";
constant TMR0_ADDR : std_logic_vector(2 downto 0) := "001";
constant PCL_ADDR : std_logic_vector(2 downto 0) := "010";
constant STATUS_ADDR : std_logic_vector(2 downto 0) := "011";
constant FSR_ADDR : std_logic_vector(2 downto 0) := "100";
constant PORTA_ADDR : std_logic_vector(2 downto 0) := "101";
constant PORTB_ADDR : std_logic_vector(2 downto 0) := "110";
constant PORTC_ADDR : std_logic_vector(2 downto 0) := "111";
constant PORTD_ADDR : std_logic_vector(2 downto 0) := "111";

-- signal definitions
signal inst : std_logic_vector(15 downto
0);

signal inst_k : std_logic_vector(7 downto 0);
signal inst_fsel : std_logic_vector(4 downto 0);
signal inst_d : std_logic;
signal inst_b : std_logic_vector(2 downto 0);
signal tmr0 : std_logic_vector(1 downto 0);
signal pc,next_pc : std_logic_vector(31 downto
0);
signal pc_load_stack : std_logic_vector(10 downto
0);
signal pc_write : std_logic_vector(10 downto
0);

signal stacklevel : std_logic_vector(1 downto 0);
signal stack1,stack2 : std_logic_vector(10 downto
0);

signal porta_dout : std_logic_vector(7 downto 0);
signal portb_dout : std_logic_vector(7 downto 0);
signal portc_dout : std_logic_vector(7 downto 0);
signal portd_dout : std_logic_vector(7 downto 0);

signal porta_din : std_logic_vector(7 downto 0);
signal portb_din : std_logic_vector(7 downto 0);
signal portc_din : std_logic_vector(7 downto 0);
signal portd_din : std_logic_vector(7 downto 0);

signal dbus,sbus : std_logic_vector(7 downto 0);
signal sbus_swap : std_logic_vector(7 downto 0);
signal sbus_mux_out : std_logic_vector(7 downto 0);

-- inst decode
signal regfile_sel,special_sel : std_logic;
signal fileaddr_indirect : std_logic;
signal fileaddr_mux1 : std_logic_vector(6 downto 0);
signal fileaddr_mux0 : std_logic_vector(6 downto 0);

signal istris,isoption : std_logic;
signal fwe,wwe,zwe,dcwe,cwe : std_logic;
signal bdpol,status1 : std_logic;
signal bd,trisa,trisb,trisc,trisd :
std_logic_vector(7 downto 0);
signal skip : std_logic;

-- alu
signal alu_asel,alu_bsel : std_logic_vector(1 downto 0)
;
signal alu_addsub : std_logic_vector(1 downto 0)
;
signal alu_bit : std_logic_vector(1 downto 0)
;
signal alu_sel : std_logic_vector(1 downto 0)
;

signal alu_z,alu_dcout,alu_cout : std_logic ;
signal alu_a,alu_b : std_logic_vector(7 downto 0)
;
signal alu_out : std_logic_vector(7 downto 0);

signal regfile_we,regfile_re : std_logic;
signal regfile_in,regfile_out : std_logic_vector(7 downto 0);
signal fileaddr : std_logic_vector(6 downto 0);

begin -- architecture


u_regs : REGS
port map (
WE => regfile_we,
RE => regfile_re,
BANK => fileaddr(6 downto 5),
LOCATION => fileaddr(4 downto 0),
DIN => regfile_in,
DOUT => regfile_out,
RESET => RESET,
CLK => CLK
);

DEBUG_PC <= pc(10 downto 0);
DEBUG_INST <= inst;

-- *********** REGISTER FILE Addressing ****************

p_regfile_we_comb : process(regfile_sel,fwe,alu_asel,alu_bsel)
begin
regfile_we <= regfile_sel and fwe;
regfile_re <= '1'; -- not used
end process;

p_fileaddr_dec_comb : process(fileaddr,isoption,istris)
begin
regfile_sel <= '1'; -- everything else;
special_sel <= '0';
if (fileaddr(4 downto 3) = "00") and (isoption = '0') and (istris =

'0') then
special_sel <= '1'; -- lower 8 addresses in ALL BANKS 1 lut
end if;
end process;


p_dbus_comb : process(alu_out)
begin
dbus <= alu_out;
regfile_in <= alu_out;
end process;

p_paddr_comb : process(next_pc)
begin
PADDR <= next_pc(31 downto 0);
end process;

p_inst_assign_comb : process(inst)
begin
inst_k <= inst(7 downto 0);
inst_fsel <= inst(4 downto 0);
inst_d <= inst(5);
inst_b <= inst(7 downto 5);
end process;

p_bdec_assign_comb : process(inst_b,bdpol)
variable bdec : std_logic_vector(7 downto 0);
begin
-- 1 lut
bdec := "00000001";
case inst_b is
when "000" => bdec := "00000001";
when "001" => bdec := "00000010";
when "010" => bdec := "00000100";
when "011" => bdec := "00001000";
when "100" => bdec := "00010000";
when "101" => bdec := "00100000";
when "110" => bdec := "01000000";
when "111" => bdec := "10000000";
when others => null;
end case;
if (bdpol = '1') then
bd <= not bdec;
else
bd <= bdec;
end if;
end process;

p_inst : process(CLK,RESET)
begin
if (RESET = '1') then
inst <= "0000000000000000";
elsif CLK'event and (CLK = '1') then
if (skip = '1') then
inst <= "0000000000000000"; -- force NOP
else
inst <= PDATA;
end if;
end if;
end process;

p_skip_comb : process(inst,alu_z,fwe,special_sel,fileaddr)
begin
-- SKIP signal.
-- We want to insert the NOP instruction for the following
conditions:
-- we have modified PCL
-- GOTO,CALL and RETLW instructions
-- BTFSS instruction when aluz is HI
-- BTFSC instruction when aluz is LO
skip <= '0';

if (fwe = '1') and (special_sel = '1') and (fileaddr(2 downto 0) =
PCL_ADDR) then skip <= '1'; end if;
if (inst(11 downto 10) = "10") then skip <= '1'; end if;
if (inst(11 downto = "0110") and (alu_z = '1') then skip <=
'1'; end if; -- BTFSC
if (inst(11 downto = "0111") and (alu_z = '0') then skip <=
'1'; end if; -- BTFSS
if (inst(11 downto 6) = "001011") and (alu_z = '1') then skip <=
'1'; end if; -- DECFSZ
if (inst(11 downto 6) = "001111") and (alu_z = '1') then skip <=
'1'; end if; -- INCFSZ
end process;

sbus_swap <= sbus(3 downto 0) & sbus(7 downto 4);


port_in : process(CLK,RESET,PORTA_IN,PORTB_IN,PORTC_IN)
begin
-- the input registers don't exist in the real device,
-- so if you read an output we have introduced a clock delay.
if (RESET = '1') then
porta_din <= (others => '0');
portb_din <= (others => '0');
portc_din <= (others => '0');
portd_din <= (others => '0');
elsif CLK'event and (CLK = '1') then -- comment this out for
combinatorial ip
porta_din <= PORTA_IN;
portb_din <= PORTB_IN;
portc_din <= PORTC_IN;
portd_din <= PORTD_IN;
end if;
end process;

p_port_reg : process(CLK,RESET)
begin
if (RESET = '1') then
trisa <= "11111111"; -- default tristate
trisb <= "11111111"; -- default tristate
trisc <= "11111111"; -- default tristate
trisd <= "11111111"; -- default tristate
porta_dout <= x"00";
portb_dout <= x"00";
portc_dout <= x"00";
portd_dout <= x"00";
elsif CLK'event and (CLK = '1') then

if (fwe = '1') and (fileaddr(2 downto 0) = PORTA_ADDR) then
if (istris = '0') and (special_sel = '1') then
porta_dout <= dbus;
elsif (istris = '1') then
trisa <= dbus;
end if;
end if;

if (fwe = '1') and (fileaddr(2 downto 0) = PORTB_ADDR) then
if (istris = '0') and (special_sel = '1') then
portb_dout <= dbus;
elsif (istris = '1') then
trisb <= dbus;
end if;
end if;

if (fwe = '1') and (fileaddr(2 downto 0) = PORTC_ADDR) then
if (istris = '0') and (special_sel = '1') then
portc_dout <= dbus;
elsif (istris = '1') then
trisc <= dbus;
end if;
end if;
if (fwe = '1') and (fileaddr(2 downto 0) = PORTD_ADDR) then
if (istris = '0') and (special_sel = '1') then
portd_dout <= dbus;
elsif (istris = '1') then
trisd <= dbus;
end if;
end if;

end if;
end process;

-- ********** PC AND STACK *************************



p_stack_comb : process(stacklevel,stack1,stack2)
begin
pc_load_stack <= stack1; -- default
case stacklevel is
when "00" => pc_load_stack <= stack1;
when "01" => pc_load_stack <= stack1;
when "10" => pc_load_stack <= stack2;
when "11" => pc_load_stack <= stack2;
when others => null;
end case;
end process;

p_stack_reg : process(CLK,RESET)
begin
if (RESET = '1') then
stack1 <= (others => '0');
stack2 <= (others => '0');
elsif CLK'event and (CLK = '1') then
if (inst(11 downto = "1001") then
case stacklevel is
when "00" => stack1 <= pc(10 downto 0);
when "01" => stack2 <= pc(10 downto 0);
when others => null;
end case;
end if;
end if;
end process;

p_stack_level : process(CLK,RESET)
begin
if (RESET = '1') then
stacklevel <= "00";
elsif CLK'event and (CLK = '1') then
stacklevel <= stacklevel;
if (inst(11 downto = "1001") then
case stacklevel is
when "00" => stacklevel <="01"; -- 1st call
when "01" => stacklevel <="10"; -- 2nd call
when "10" => stacklevel <="10"; -- already 2, ignore
when "11" => stacklevel <="00"; -- broke
when others => null;
end case;
elsif (inst(11 downto = "1000") then
case stacklevel is
when "00" => stacklevel <="00"; -- broke
when "01" => stacklevel <="00"; -- go back to no call
when "10" => stacklevel <="01"; -- go back to 1 call
when "11" => stacklevel <="10"; -- broke
when others => null;
end case;
end if;
end if;
end process;
end rtl;
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library IEEE;
use IEEE.std_logic_1164.all;

entity keyboard is
port (
Key_0: in STD_LOGIC;
Key_1: in STD_LOGIC;
Key_2: in STD_LOGIC;
Key_3: in STD_LOGIC;
Key_4: in STD_LOGIC;
Key_5: in STD_LOGIC;
Key_6: in STD_LOGIC;
Key_7: in STD_LOGIC;
Key_8: in STD_LOGIC;
Key_9: in STD_LOGIC;
RESET: in STD_LOGIC;
ACKA: in STD_LOGIC;
INTA: out STD_LOGIC;
CODE: out STD_LOGIC_VECTOR (3 downto 0)
);
end keyboard;

--}} End of automatically maintained section

architecture keyboard of keyboard is
signal INT: std_logic;
begin
-- <<enter your statements here>>
process(Key_0,Key_1,Key_2,Key_3,Key_4,Key_5,Key_6, Key_7,Key_8,Key_9,Key_0,

ACKA, RESET)
begin
if(RESET='1') then
INT<='1';
CODE<="0000";
else
if(INT='1' and (ACKA='1' or ACKA='H')) then
if(Key_0='1') then
CODE<="0000";
INT<='0';
elsif(Key_1='1') then
CODE<="0001";
INT<='0';
elsif(Key_2='1') then
CODE<="0010";
INT<='0';
elsif(Key_3='1') then
CODE<="0011";
INT<='0';
elsif(Key_4='1') then
CODE<="0100";
INT<='0';
elsif(Key_5='1') then
CODE<="0101";
INT<='0';
elsif(Key_6='1') then
CODE<="0110";
INT<='0';
elsif(Key_7='1') then
CODE<="0111";
INT<='0';
elsif(Key_8='1') then
CODE<="1000";
INT<='0';
elsif(Key_9='1') then
CODE<="1001";
INT<='0';
else
INT<='1';
end if;
elsif(INT='0' and ACKA='0') then
INT<='1';
end if;
end if;
end process;

INTA<=INT;
end keyboard;
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library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;
use work.pkg_xilinx_prims.all;

entity RISC5X_XIL is
port (
I_PRAM_ADDR : in std_logic_vector(31 downto 0);
I_PRAM_DIN : in std_logic_vector(15 downto 0);
O_PRAM_DOUT : out std_logic_vector(15 downto 0);
I_PRAM_WE : in std_logic;
I_PRAM_ENA : in std_logic;
PRAM_CLK : in std_logic;
--
IO_PORTA_IO : inout std_logic_vector(7 downto 0);
IO_PORTB_IO : inout std_logic_vector(7 downto 0);
IO_PORTC_IO : inout std_logic_vector(7 downto 0);
IO_PORTD_IO : inout std_logic_vector(7 downto 0);

O_DEBUG_W : out std_logic_vector(7 downto 0);
O_DEBUG_PC : out std_logic_vector(10 downto 0);
O_DEBUG_INST : out std_logic_vector(11 downto 0);
O_DEBUG_STATUS : out std_logic_vector(7 downto 0);

RESET : in std_logic;
CLK : in std_logic
);
end;

architecture RTL of RISC5X_XIL is
signal porta_in : std_logic_vector(7 downto 0);
signal porta_out : std_logic_vector(7 downto 0);
signal porta_oe_l : std_logic_vector(7 downto 0);

signal portb_in : std_logic_vector(7 downto 0);
signal portb_out : std_logic_vector(7 downto 0);
signal portb_oe_l : std_logic_vector(7 downto 0);

signal portc_in : std_logic_vector(7 downto 0);
signal portc_out : std_logic_vector(7 downto 0);
signal portc_oe_l : std_logic_vector(7 downto 0);

signal portd_in : std_logic_vector(7 downto 0);
signal portd_out : std_logic_vector(7 downto 0);
signal portd_oe_l : std_logic_vector(7 downto 0);

signal paddr : std_logic_vector(31 downto 0);
signal pdata,pin : std_logic_vector(15 downto 0);
signal pram_addr : std_logic_vector(10 downto 0);
signal pram_din : std_logic_vector(11 downto 0);
signal pram_dout : std_logic_vector(11 downto 0);
signal pram_we : std_logic;
signal pram_ena : std_logic;

signal debug_w : std_logic_vector(7 downto 0);
signal debug_pc : std_logic_vector(10 downto 0);
signal debug_inst : std_logic_vector(15 downto 0);
signal debug_status : std_logic_vector(7 downto 0);

signal doa_temp : std_logic_vector(11 downto 0);
signal dob_temp : std_logic_vector(11 downto 0);

component CPU is
port (
PADDR : out std_logic_vector(31 downto 0);
PDATA : in std_logic_vector(15 downto 0);
O_PRAM_DOUT : out std_logic_vector(15 downto 0);
PORTA_IN : in std_logic_vector(7 downto 0);
PORTA_OUT : out std_logic_vector(7 downto 0);
PORTA_OE_L : out std_logic_vector(7 downto 0);

PORTB_IN : in std_logic_vector(7 downto 0);
PORTB_OUT : out std_logic_vector(7 downto 0);
PORTB_OE_L : out std_logic_vector(7 downto 0);

PORTC_IN : in std_logic_vector(7 downto 0);
PORTC_OUT : out std_logic_vector(7 downto 0);
PORTC_OE_L : out std_logic_vector(7 downto 0);

PORTD_IN : in std_logic_vector(7 downto 0);
PORTD_OUT : out std_logic_vector(7 downto 0);
PORTD_OE_L : out std_logic_vector(7 downto 0);

DEBUG_W : out std_logic_vector(7 downto 0);
DEBUG_PC : out std_logic_vector(10 downto 0);
DEBUG_INST : out std_logic_vector(15 downto 0);
DEBUG_STATUS : out std_logic_vector(7 downto 0);
-- out_DATA : out std_logic_vector(15 downto 0);
RESET : in std_logic;
CLK : in std_logic
);
end component;

begin
u0 : CPU
port map (
PADDR => paddr,
PDATA => pdata,
O_PRAM_DOUT => pin,
PORTA_IN => porta_in,
PORTA_OUT => porta_out,
PORTA_OE_L => porta_oe_l,

PORTB_IN => portb_in,
PORTB_OUT => portb_out,
PORTB_OE_L => portb_oe_l,

PORTC_IN => portc_in,
PORTC_OUT => portc_out,
PORTC_OE_L => portc_oe_l,

PORTD_IN => portd_in,
PORTD_OUT => portd_out,
PORTD_OE_L => portd_oe_l,

-- DEBUG_W => debug_w,
-- DEBUG_PC => debug_pc,
-- DEBUG_INST => debug_inst,
-- DEBUG_STATUS => debug_status,

RESET => RESET,
CLK => CLK
);

p_drive_ports_out_comb :
process(porta_out,porta_oe_l,portb_out,portb_oe_l, portc_out,portc_oe_l)
begin
pin<= I_PRAM_DIN;
for i in 0 to 7 loop
if (porta_oe_l(i) = '0') then
IO_PORTA_IO(i) <= porta_out(i);
else
IO_PORTA_IO(i) <= 'Z';
end if;

if (portb_oe_l(i) = '0') then
IO_PORTB_IO(i) <= portb_out(i);
else
IO_PORTB_IO(i) <= 'Z';
end if;

if (portc_oe_l(i) = '0') then
IO_PORTC_IO(i) <= portc_out(i);
else
IO_PORTC_IO(i) <= 'Z';
end if;
if (portd_oe_l(i) = '0') then
IO_PORTD_IO(i) <= portd_out(i);
else
IO_PORTD_IO(i) <= 'Z';
end if;
end loop;
end process;

p_drive_ports_in_comb : process(IO_PORTA_IO,IO_PORTB_IO,IO_PORTC_IO)
begin
O_PRAM_DOUT <= pin;
porta_in <= IO_PORTA_IO;
portb_in <= IO_PORTB_IO;
portc_in <= IO_PORTC_IO;
portd_in <= IO_PORTC_IO;
end process;
end RTL;
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--HEADER FILE INTILI SATION
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;
use work.pkg_xilinx_prims.all;


--There are three memory blocks in each of the risc devices.
--The program memory and data
--memory have separate buses so that concurrent
---access can occur and is detailed in this section. The
--EEPROM data memory block is detailed in
--"Data EEPROM and Flash Program Memory".
--Additional information on device memory may be found

--The data memory is partitioned into multiple banks
--which contain the General Purpose Registers and the
--Special Function Registers. Bits RP1 (Status<6>) and
--R-P0 (Status<5>) are the bank select bits.
--REGISTER INPUT OUTPUT DECLARATION
entity REGS is
port (
WE : in std_logic;
RE : in std_logic;
BANK : in std_logic_vector(1 downto 0);
LOCATION : in std_logic_vector(4 downto 0);
DIN : in std_logic_vector(7 downto 0);
DOUT : out std_logic_vector(7 downto 0);
RESET : in std_logic;
CLK : in std_logic
);
end;
--

architecture RTL of REGS is

constant WIDTH : natural := 8;
constant OP_REG : boolean := false;

type slv_array is array (natural range <>) of
std_logic_vector(WIDTH-1 downto 0);
signal ram_out : slv_array(4 downto 0);
signal wen_int : std_logic_vector(4 downto 0);
signal sel : std_logic_vector(2 downto 0);
signal final_addr : std_logic_vector(6 downto 0);
--constant WIDTH : natural := 8;
--constant OP_REG : boolean := false;

-- following required for simulation model only
constant nwords : integer := 2 ** 7;
type ram_type is array (0 to nwords-1) of std_logic_vector(WIDTH-1
downto 0);
signal ram_read_data : std_logic_vector(WIDTH-1 downto 0);
--shared variable ram :ram_type := (others => (others => 'X')); --
helps debug no end!
shared variable ram :ram_type := (others => (others => '0'));

begin -- architecture

-- ram mapping
-- bank location
-- xx 00xxx special registers
-- xx 01xxx common 8 to all banks
-- 00 1xxxx 16 bank 0
-- 01 1xxxx 16 bank 1
-- 10 1xxxx 16 bank 2
-- 11 1xxxx 16 bank 3
DOUT<= DIN;
p_wen_comb : process (BANK,LOCATION,WE)
variable addr : std_logic_vector(3 downto 0);
begin
addr := (BANK & LOCATION(4 downto 3));
wen_int <= (others => '0');
case addr(3 downto 1) is
when "001" => wen_int(0) <= WE; -- bank0
when "011" => wen_int(1) <= WE; -- bank1
when "101" => wen_int(2) <= WE; -- bank2
when "111" => wen_int(3) <= WE; -- bank3

when others => null;
end case;
if (LOCATION(4 downto 3) = "01") then
wen_int(4) <= WE; -- common
end if;


SEL <= BANK & LOCATION(4);

end process;

--pragma translate_off


--The PIC16F87XA devices have a 13-bit program
--counter capable of addressing an 8K word x 14 bit
--program memory space. The risc
--devices have 8K words x 14 bits of Flash program
--memory,

p_remap : process(BANK,LOCATION)
variable addr : std_logic_vector(3 downto 0);
begin
addr := (BANK & LOCATION(4 downto 3));
final_addr <= "0000000";
case addr is
when "0001" => final_addr <= "0000" & LOCATION(2 downto 0);
when "0101" => final_addr <= "0000" & LOCATION(2 downto 0);
when "1001" => final_addr <= "0000" & LOCATION(2 downto 0);
when "1101" => final_addr <= "0000" & LOCATION(2 downto 0);
-- bank #0
when "0010" => final_addr <= "0001" & LOCATION(2 downto 0);
when "0011" => final_addr <= "0010" & LOCATION(2 downto 0);
-- bank #1
when "0110" => final_addr <= "0011" & LOCATION(2 downto 0);
when "0111" => final_addr <= "0100" & LOCATION(2 downto 0);
--bank #2
when "1010" => final_addr <= "0101" & LOCATION(2 downto 0);
when "1011" => final_addr <= "0110" & LOCATION(2 downto 0);
-- bank #3
when "1110" => final_addr <= "0111" & LOCATION(2 downto 0);
when "1111" => final_addr <= "1000" & LOCATION(2 downto 0);
when others => null;
end case;
end process;
end RTL;

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