| Line 68... |
Line 68... |
end process;
|
end process;
|
|
|
-- Next state logic (Execution states)
|
-- Next state logic (Execution states)
|
process (clk, currentCpuState)
|
process (clk, currentCpuState)
|
begin
|
begin
|
if ( (currentCpuState /= execute) and (currentCpuState /= executing) ) then
|
if (reset = '1') then
|
currentExState <= initInstructionExecution;
|
currentExState <= initInstructionExecution;
|
elsif rising_edge(clk) then
|
elsif rising_edge(clk) then
|
currentExState <= nextExState;
|
currentExState <= nextExState;
|
end if;
|
end if;
|
end process;
|
end process;
|
| Line 185... |
Line 185... |
operand_imm := IR((IR'HIGH - 10) downto (IR'LOW)); -- 22 bits imediate value (Max value 4194304)
|
operand_imm := IR((IR'HIGH - 10) downto (IR'LOW)); -- 22 bits imediate value (Max value 4194304)
|
|
|
-- Select the instruction and init it's execution
|
-- Select the instruction and init it's execution
|
case currentExState is
|
case currentExState is
|
when initInstructionExecution =>
|
when initInstructionExecution =>
|
|
nextExState <= waitToExecute;
|
|
|
|
when waitToExecute =>
|
|
if ( (currentCpuState /= execute) and (currentCpuState /= executing) ) then
|
|
nextExState <= initInstructionExecution;
|
|
else
|
case opcodeIR is
|
case opcodeIR is
|
-- MOV r2,r1 (See the testDatapath to see how to drive the datapath for this function)
|
-- MOV r2,r1 (See the testDatapath to see how to drive the datapath for this function)
|
when mov_reg =>
|
when mov_reg =>
|
MuxDp <= muxPos(fromRegFileB);
|
MuxDp <= muxPos(fromRegFileB);
|
DpRegFileReadAddrB <= Num2reg(conv_integer(UNSIGNED(operand_reg2)));
|
DpRegFileReadAddrB <= Num2reg(conv_integer(UNSIGNED(operand_reg2)));
|
| Line 243... |
Line 249... |
nextExState <= writeRegister;
|
nextExState <= writeRegister;
|
|
|
when others =>
|
when others =>
|
null;
|
null;
|
end case;
|
end case;
|
|
end if;
|
|
|
-- Write something on the register files
|
-- Write something on the register files
|
when writeRegister =>
|
when writeRegister =>
|
DpRegFileWriteEn <= '1';
|
DpRegFileWriteEn <= '1';
|
nextExState <= releaseWriteRead;
|
nextExState <= releaseWriteRead;
|
| Line 265... |
Line 272... |
when releaseWriteRead =>
|
when releaseWriteRead =>
|
DpRegFileReadEnB <= '0';
|
DpRegFileReadEnB <= '0';
|
DpRegFileReadEnA <= '0';
|
DpRegFileReadEnA <= '0';
|
DpRegFileWriteEn <= '0';
|
DpRegFileWriteEn <= '0';
|
outEnDp <= disable;
|
outEnDp <= disable;
|
|
-- Come back to waiting state
|
|
nextExState <= waitToExecute;
|
|
|
when others =>
|
when others =>
|
null;
|
null;
|
end case;
|
end case;
|
end process;
|
end process;
|
