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Add all instructions support + bubbles (wip)

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This commit is contained in:
Simard Yohan 2021-05-04 14:57:53 +02:00
parent 267630c1b1
commit fd03450f1c
6 changed files with 369 additions and 45 deletions
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4
.gitignore vendored
View file

@ -6,3 +6,7 @@
# Except vhdl files
!.gitignore
!*.vhd
# and simulation config files
!*.wcfg

20
ALU.vhd
View file

@ -14,6 +14,10 @@ entity ALU is
end ALU;
architecture Behavioral of ALU is
constant Ctrl_ADD : STD_LOGIC_VECTOR (1 downto 0) := "01";
constant Ctrl_MUL : STD_LOGIC_VECTOR (1 downto 0) := "10";
constant Ctrl_SOU : STD_LOGIC_VECTOR (1 downto 0) := "11";
SIGNAL aux : STD_LOGIC_VECTOR (7 downto 0);
SIGNAL A9 : STD_LOGIC_VECTOR (8 downto 0);
SIGNAL B9 : STD_LOGIC_VECTOR (8 downto 0);
@ -26,15 +30,15 @@ begin
ADD <= A9 + B9;
SUB <= A9 - B9;
MUL <= A * B;
aux <= ADD(7 downto 0) when Ctrl = "01" else
SUB(7 downto 0) when Ctrl = "10" else
MUL(7 downto 0) when Ctrl = "11" else
(others => '0');
O <= ADD(8) when Ctrl = "01" else
'0' when Ctrl = "11" and MUL(15 downto 8) = "00000000" else
'1' when Ctrl = "11" else
aux <= ADD(7 downto 0) when Ctrl = Ctrl_ADD else
SUB(7 downto 0) when Ctrl = Ctrl_SOU else
MUL(7 downto 0) when Ctrl = Ctrl_MUL else
(others => '0');
O <= ADD(8) when Ctrl = Ctrl_ADD else
'0' when Ctrl = Ctrl_MUL and MUL(15 downto 8) = "00000000" else
'1' when Ctrl = Ctrl_MUL else
'0';
C <= ADD(8) when Ctrl = "01" else '0';
C <= ADD(8) when Ctrl = Ctrl_ADD else '0';
Z <= '1' when aux = "00000000" else '0';
S <= aux;
end Behavioral;

102
CPU.vhd
View file

@ -1,6 +1,7 @@
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.NUMERIC_STD.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity CPU is
Port (
@ -10,8 +11,20 @@ entity CPU is
end CPU;
architecture Behavioral of CPU is
constant NOP : std_logic_vector(7 downto 0) := "00000000";
constant ADD : std_logic_vector(7 downto 0) := "00000001";
constant MUL : std_logic_vector(7 downto 0) := "00000010";
constant SOU : std_logic_vector(7 downto 0) := "00000011";
constant DIV : std_logic_vector(7 downto 0) := "00000100";
constant COP : std_logic_vector(7 downto 0) := "00000101";
constant AFC : std_logic_vector(7 downto 0) := "00000110";
constant HALT : std_logic_vector(7 downto 0) := "00000000";
constant LOAD : std_logic_vector(7 downto 0) := "00000111";
constant STORE: std_logic_vector(7 downto 0) := "00001000";
-- constant HALT : std_logic_vector(7 downto 0) := "00001001";
constant MX1: std_logic_vector(8 downto 0) := "100111110";
constant MX2: std_logic_vector(8 downto 0) := "000011110";
constant needBubbles: std_logic_vector(8 downto 0) := "111111110";
COMPONENT ALU
PORT(
@ -73,7 +86,7 @@ architecture Behavioral of CPU is
signal registers_addr_A : std_logic_vector(3 downto 0);
signal registers_addr_B : std_logic_vector(3 downto 0);
signal registers_addr_W : std_logic_vector(3 downto 0);
signal registers_W : std_logic;
signal registers_W : std_logic := '0';
signal registers_DATA : std_logic_vector(7 downto 0);
signal registers_QA : std_logic_vector(7 downto 0);
signal registers_QB : std_logic_vector(7 downto 0);
@ -109,8 +122,7 @@ architecture Behavioral of CPU is
signal A4 : STD_LOGIC_VECTOR(7 downto 0);
signal B4 : STD_LOGIC_VECTOR(7 downto 0);
-- Etage 5
signal bubble : integer := 2;
begin
myalu: ALU PORT MAP (
@ -150,47 +162,71 @@ begin
clk => clk
);
instr_memory_addr <= IP;
registers_addr_W <= A4(3 downto 0);
registers_W <= '0' when (OP4 = NOP or OP4 = STORE) else '1';
registers_data <= B4;
registers_addr_A <= B1(3 downto 0);
registers_addr_B <= C1(3 downto 0);
ALU_A <= B2;
ALU_B <= C2;
ALU_Ctrl <= OP2(1 downto 0);
data_memory_RW <= '0' when (OP3 = STORE) else '1';
data_memory_addr <= A3 when (OP3 = STORE) else B3;
data_memory_data <= B3;
process
begin
wait until CLK'event and CLK='1';
if (halted = '0') then
-- Etage 5
registers_addr_W <= A4(3 downto 0);
if OP4 = AFC then
registers_W <= '1';
elsif OP4 = HALT then
halted <= '1';
else
registers_W <= '0';
end if;
registers_data <= B4;
-- Etage 4
-- Etage 3 -> 4
OP4 <= OP3;
A4 <= A3;
B4 <= B3;
-- Etage 3
if (OP3 = LOAD) then
B4 <= data_memory_Q;
else
B4 <= B3;
end if;
-- Etage 2 -> 3
OP3 <= OP2;
A3 <= A2;
B3 <= B2;
-- Etage 2
if (MX2(to_integer(unsigned(OP2))) = '1') then
B3 <= ALU_S;
else
B3 <= B2;
end if;
-- Etage 1 -> 2
OP2 <= OP1;
A2 <= A1;
B2 <= B1;
C2 <= C1;
if (MX1(to_integer(unsigned(OP1))) = '1') then
B2 <= registers_QA;
else
B2 <= B1;
end if;
C2 <= registers_QB;
-- Etage 1
instr_memory_addr <= IP;
C1 <= instr_memory_q(7 downto 0);
B1 <= instr_memory_q(15 downto 8);
A1 <= instr_memory_q(23 downto 16);
OP1 <= instr_memory_q(31 downto 24);
-- IP <= IP + 1;
-- Memoire -> etage 1
if (bubble = 0) then
C1 <= instr_memory_q(7 downto 0);
B1 <= instr_memory_q(15 downto 8);
A1 <= instr_memory_q(23 downto 16);
OP1 <= instr_memory_q(31 downto 24);
IP <= IP + 1;
if (needBubbles(to_integer(unsigned(instr_memory_q(31 downto 24)))) = '1') then
bubble <= 3;
end if;
else
C1 <= "00000000";
B1 <= "00000000";
A1 <= "00000000";
OP1 <= NOP;
bubble <= bubble - 1;
end if;
end if;
end process;

260
config_simu.wcfg Normal file
View file

@ -0,0 +1,260 @@
<?xml version="1.0" encoding="UTF-8"?>
<wave_config>
<wave_state>
</wave_state>
<db_ref_list>
<db_ref path="/home/ysimard/Documents/4A/projet_compilateur/processor-2000/CPU_test_isim_beh.wdb" id="1" type="auto">
<top_modules>
<top_module name="cpu_test" />
<top_module name="numeric_std" />
<top_module name="std_logic_1164" />
<top_module name="std_logic_arith" />
<top_module name="std_logic_unsigned" />
</top_modules>
</db_ref>
</db_ref_list>
<WVObjectSize size="11" />
<wvobject fp_name="/cpu_test/clk" type="logic" db_ref_id="1">
<obj_property name="ElementShortName">clk</obj_property>
<obj_property name="ObjectShortName">clk</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/rst" type="logic" db_ref_id="1">
<obj_property name="ElementShortName">rst</obj_property>
<obj_property name="ObjectShortName">rst</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/clk_period" type="other" db_ref_id="1">
<obj_property name="ElementShortName">clk_period</obj_property>
<obj_property name="ObjectShortName">clk_period</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/ip" type="array" db_ref_id="1">
<obj_property name="ElementShortName">ip[7:0]</obj_property>
<obj_property name="ObjectShortName">ip[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="group39" type="group">
<obj_property name="label">etage 1</obj_property>
<obj_property name="DisplayName">label</obj_property>
<wvobject fp_name="/cpu_test/uut/bubble" type="other" db_ref_id="1">
<obj_property name="DisplayName">label</obj_property>
<obj_property name="ElementShortName">bubble</obj_property>
<obj_property name="ObjectShortName">bubble</obj_property>
<obj_property name="label">bubble</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/op1" type="array" db_ref_id="1">
<obj_property name="ElementShortName">op1[7:0]</obj_property>
<obj_property name="ObjectShortName">op1[7:0]</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#ff00ff</obj_property>
<obj_property name="Radix">HEXRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/a1" type="array" db_ref_id="1">
<obj_property name="ElementShortName">a1[7:0]</obj_property>
<obj_property name="ObjectShortName">a1[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/b1" type="array" db_ref_id="1">
<obj_property name="ElementShortName">b1[7:0]</obj_property>
<obj_property name="ObjectShortName">b1[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/c1" type="array" db_ref_id="1">
<obj_property name="ElementShortName">c1[7:0]</obj_property>
<obj_property name="ObjectShortName">c1[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="group40" type="group">
<obj_property name="label">etage 2</obj_property>
<obj_property name="DisplayName">label</obj_property>
<wvobject fp_name="/cpu_test/uut/op2" type="array" db_ref_id="1">
<obj_property name="ElementShortName">op2[7:0]</obj_property>
<obj_property name="ObjectShortName">op2[7:0]</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#ff00ff</obj_property>
<obj_property name="Radix">HEXRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/a2" type="array" db_ref_id="1">
<obj_property name="ElementShortName">a2[7:0]</obj_property>
<obj_property name="ObjectShortName">a2[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/b2" type="array" db_ref_id="1">
<obj_property name="ElementShortName">b2[7:0]</obj_property>
<obj_property name="ObjectShortName">b2[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/c2" type="array" db_ref_id="1">
<obj_property name="ElementShortName">c2[7:0]</obj_property>
<obj_property name="ObjectShortName">c2[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="group41" type="group">
<obj_property name="label">etage 3</obj_property>
<obj_property name="DisplayName">label</obj_property>
<wvobject fp_name="/cpu_test/uut/op3" type="array" db_ref_id="1">
<obj_property name="ElementShortName">op3[7:0]</obj_property>
<obj_property name="ObjectShortName">op3[7:0]</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#ff00ff</obj_property>
<obj_property name="Radix">HEXRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/a3" type="array" db_ref_id="1">
<obj_property name="ElementShortName">a3[7:0]</obj_property>
<obj_property name="ObjectShortName">a3[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/b3" type="array" db_ref_id="1">
<obj_property name="ElementShortName">b3[7:0]</obj_property>
<obj_property name="ObjectShortName">b3[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="group42" type="group">
<obj_property name="label">etage 4</obj_property>
<obj_property name="DisplayName">label</obj_property>
<wvobject fp_name="/cpu_test/uut/op4" type="array" db_ref_id="1">
<obj_property name="ElementShortName">op4[7:0]</obj_property>
<obj_property name="ObjectShortName">op4[7:0]</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#ff00ff</obj_property>
<obj_property name="Radix">HEXRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/a4" type="array" db_ref_id="1">
<obj_property name="ElementShortName">a4[7:0]</obj_property>
<obj_property name="ObjectShortName">a4[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/b4" type="array" db_ref_id="1">
<obj_property name="ElementShortName">b4[7:0]</obj_property>
<obj_property name="ObjectShortName">b4[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="group62" type="group">
<obj_property name="label">registres</obj_property>
<obj_property name="DisplayName">label</obj_property>
<wvobject fp_name="/cpu_test/uut/reg/rb" type="array" db_ref_id="1">
<obj_property name="ElementShortName">rb[15:0]</obj_property>
<obj_property name="ObjectShortName">rb[15:0]</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#00ffff</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
<wvobject fp_name="/cpu_test/uut/reg/rb[15]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[15]</obj_property>
<obj_property name="ObjectShortName">rb[15]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[14]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[14]</obj_property>
<obj_property name="ObjectShortName">rb[14]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[13]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[13]</obj_property>
<obj_property name="ObjectShortName">rb[13]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[12]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[12]</obj_property>
<obj_property name="ObjectShortName">rb[12]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[11]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[11]</obj_property>
<obj_property name="ObjectShortName">rb[11]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[10]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[10]</obj_property>
<obj_property name="ObjectShortName">rb[10]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[9]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[9]</obj_property>
<obj_property name="ObjectShortName">rb[9]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[8]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[8]</obj_property>
<obj_property name="ObjectShortName">rb[8]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[7]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[7]</obj_property>
<obj_property name="ObjectShortName">rb[7]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[6]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[6]</obj_property>
<obj_property name="ObjectShortName">rb[6]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[5]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[5]</obj_property>
<obj_property name="ObjectShortName">rb[5]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[4]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[4]</obj_property>
<obj_property name="ObjectShortName">rb[4]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[3]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[3]</obj_property>
<obj_property name="ObjectShortName">rb[3]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[2]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[2]</obj_property>
<obj_property name="ObjectShortName">rb[2]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[1]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[1]</obj_property>
<obj_property name="ObjectShortName">rb[1]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/rb[0]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[0]</obj_property>
<obj_property name="ObjectShortName">rb[0]</obj_property>
<obj_property name="Radix">SIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/addr_a" type="array" db_ref_id="1">
<obj_property name="ElementShortName">addr_a[3:0]</obj_property>
<obj_property name="ObjectShortName">addr_a[3:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/addr_w" type="array" db_ref_id="1">
<obj_property name="DisplayName">label</obj_property>
<obj_property name="ElementShortName">addr_w[3:0]</obj_property>
<obj_property name="ObjectShortName">addr_w[3:0]</obj_property>
<obj_property name="label">addr_w[3:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/w" type="logic" db_ref_id="1">
<obj_property name="ElementShortName">w</obj_property>
<obj_property name="ObjectShortName">w</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/reg/data" type="array" db_ref_id="1">
<obj_property name="ElementShortName">data[7:0]</obj_property>
<obj_property name="ObjectShortName">data[7:0]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
</wvobject>
</wvobject>
<wvobject fp_name="/cpu_test/uut/data_mem/memory[8]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[8]</obj_property>
<obj_property name="ObjectShortName">memory[8]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#008080</obj_property>
</wvobject>
<wvobject fp_name="/cpu_test/uut/data_mem/memory[20]" type="array" db_ref_id="1">
<obj_property name="ElementShortName">[20]</obj_property>
<obj_property name="ObjectShortName">memory[20]</obj_property>
<obj_property name="Radix">UNSIGNEDDECRADIX</obj_property>
<obj_property name="UseCustomSignalColor">true</obj_property>
<obj_property name="CustomSignalColor">#008080</obj_property>
</wvobject>
</wave_config>

6
data_memory.vhd
View file

@ -22,9 +22,9 @@ begin
memory <= (others => (others => '0'));
elsif (rw = '0') then
memory(to_integer(unsigned(addr))) <= data;
else
q <= memory(to_integer(unsigned(addr)));
end if;
end process;
end Behavioral;
q <= memory(to_integer(unsigned(addr)));
end Behavioral;

22
instruction_memory.vhd
View file

@ -9,8 +9,28 @@ entity instruction_memory is
end instruction_memory;
architecture Behavioral of instruction_memory is
constant NOP : std_logic_vector(7 downto 0) := "00000000";
constant ADD : std_logic_vector(7 downto 0) := "00000001";
constant MUL : std_logic_vector(7 downto 0) := "00000010";
constant SOU : std_logic_vector(7 downto 0) := "00000011";
constant DIV : std_logic_vector(7 downto 0) := "00000100";
constant COP : std_logic_vector(7 downto 0) := "00000101";
constant AFC : std_logic_vector(7 downto 0) := "00000110";
constant LOAD : std_logic_vector(7 downto 0) := "00000111";
constant STORE: std_logic_vector(7 downto 0) := "00001000";
type MEMORY_TYPE is array (256 downto 0) of std_logic_vector(31 downto 0);
signal memory: MEMORY_TYPE := (0 => "00000110000000010000001000000000", others => (others => '0'));
signal memory: MEMORY_TYPE := (
1 => AFC & "00000001" & "00000010" & "00000000", -- r1 <= 2
2 => COP & "00000011" & "00000001" & "00000000", -- r3 <= r1 (= 2)
3 => ADD & "00000100" & "00000001" & "00000011", -- 2 + 2 = 4 dans R4
4 => MUL & "00000101" & "00000100" & "00000001", -- 4 * 2 = 8 dans R5
5 => SOU & "00000010" & "00000101" & "00000100", -- 8 - 4 = 4 dans R2
6 => STORE & "00001000" & "00000010" & "00000000", -- store R2 (4) at address 8
7 => STORE & "00010100" & "00000101" & "00000000", -- store R5 (8) at address 20
8 => LOAD & "00000111" & "00001000" & "00000000", -- load mem@8 (4) in R7
9 => LOAD & "00001000" & "00010100" & "00000000", -- load mem@20 (8) in R8
others => (others => '0'));
begin
process
begin