mirror of
https://github.com/Gehstock/Mist_FPGA.git
synced 2026-02-16 20:51:00 +00:00
423 lines
19 KiB
VHDL
423 lines
19 KiB
VHDL
-------------------------------------------------------------------------------
|
|
--
|
|
-- The Opcode Decoder Table.
|
|
-- Decodes the given opcode to instruction mnemonics.
|
|
-- Also derives the multicycle information.
|
|
--
|
|
-- $Id: opc_table.vhd,v 1.3 2004/07/11 16:51:33 arniml Exp $
|
|
--
|
|
-- Copyright (c) 2004, Arnim Laeuger (arniml@opencores.org)
|
|
--
|
|
-- All rights reserved
|
|
--
|
|
-- Redistribution and use in source and synthezised forms, with or without
|
|
-- modification, are permitted provided that the following conditions are met:
|
|
--
|
|
-- Redistributions of source code must retain the above copyright notice,
|
|
-- this list of conditions and the following disclaimer.
|
|
--
|
|
-- Redistributions in synthesized form must reproduce the above copyright
|
|
-- notice, this list of conditions and the following disclaimer in the
|
|
-- documentation and/or other materials provided with the distribution.
|
|
--
|
|
-- Neither the name of the author nor the names of other contributors may
|
|
-- be used to endorse or promote products derived from this software without
|
|
-- specific prior written permission.
|
|
--
|
|
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
-- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
|
|
-- THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
-- PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE
|
|
-- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
-- CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
-- SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
-- INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
-- CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
-- ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
-- POSSIBILITY OF SUCH DAMAGE.
|
|
--
|
|
-- Please report bugs to the author, but before you do so, please
|
|
-- make sure that this is not a derivative work and that
|
|
-- you have the latest version of this file.
|
|
--
|
|
-- The latest version of this file can be found at:
|
|
-- http://www.opencores.org/cvsweb.shtml/t48/
|
|
--
|
|
-------------------------------------------------------------------------------
|
|
|
|
library ieee;
|
|
use ieee.std_logic_1164.all;
|
|
|
|
use work.t48_pack.word_t;
|
|
use work.decoder_pack.mnemonic_t;
|
|
|
|
entity opc_table is
|
|
|
|
port (
|
|
opcode_i : in word_t;
|
|
multi_cycle_o : out std_logic;
|
|
mnemonic_o : out mnemonic_t
|
|
);
|
|
|
|
end opc_table;
|
|
|
|
|
|
use work.decoder_pack.all;
|
|
|
|
architecture rtl of opc_table is
|
|
|
|
begin
|
|
|
|
-----------------------------------------------------------------------------
|
|
-- Process opc_decode
|
|
--
|
|
-- Purpose:
|
|
-- Decode the opcode to the set of mnemonics.
|
|
--
|
|
opc_decode: process (opcode_i)
|
|
begin
|
|
-- default assignment
|
|
mnemonic_o <= MN_NOP;
|
|
multi_cycle_o <= '0';
|
|
|
|
case opcode_i is
|
|
-- Mnemonic ADD ---------------------------------------------------------
|
|
when "01101000" | "01101001" | "01101010" | "01101011" | -- ADD A, Rr
|
|
"01101100" | "01101101" | "01101110" | "01101111" | --
|
|
"01100000" | "01100001" | -- ADD A, @ Rr
|
|
"01111000" | "01111001" | "01111010" | "01111011" | -- ADDC A, Rr
|
|
"01111100" | "01111101" | "01111110" | "01111111" | --
|
|
"01110000" | "01110001" => -- ADDC A, @ Rr
|
|
mnemonic_o <= MN_ADD;
|
|
|
|
-- Mnemonic ADD_A_DATA --------------------------------------------------
|
|
when "00000011" | -- ADD A, data
|
|
"00010011" => -- ADDC A, data
|
|
mnemonic_o <= MN_ADD_A_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic ANL ---------------------------------------------------------
|
|
when "01011000" | "01011001" | "01011010" | "01011011" | -- ANL A, Rr
|
|
"01011100" | "01011101" | "01011110" | "01011111" | --
|
|
"01010000" | "01010001" => -- ANL A, @ Rr
|
|
mnemonic_o <= MN_ANL;
|
|
|
|
-- Mnemonic ANL_A_DATA --------------------------------------------------
|
|
when "01010011" => -- ANL A, data
|
|
mnemonic_o <= MN_ANL_A_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic ANL_EXT -----------------------------------------------------
|
|
when "10011000" | -- ANL BUS, data
|
|
"10011001" | "10011010" => -- ANL PP, data
|
|
mnemonic_o <= MN_ANL_EXT;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic CALL --------------------------------------------------------
|
|
when "00010100" | "00110100" | "01010100" | "01110100" | -- CALL addr
|
|
"10010100" | "10110100" | "11010100" | "11110100" => --
|
|
mnemonic_o <= MN_CALL;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic CLR_A -------------------------------------------------------
|
|
when "00100111" => -- CLR A
|
|
mnemonic_o <= MN_CLR_A;
|
|
|
|
-- Mnemonic CLR_C -------------------------------------------------------
|
|
when "10010111" => -- CLR C
|
|
mnemonic_o <= MN_CLR_C;
|
|
|
|
-- Mnemonic CLR_F -------------------------------------------------------
|
|
when "10000101" | -- CLR F0
|
|
"10100101" =>
|
|
mnemonic_o <= MN_CLR_F;
|
|
|
|
-- Mnemonic CPL_A -------------------------------------------------------
|
|
when "00110111" => -- CPL A
|
|
mnemonic_o <= MN_CPL_A;
|
|
|
|
-- Mnemonic CPL_C -------------------------------------------------------
|
|
when "10100111" => -- CPL C
|
|
mnemonic_o <= MN_CPL_C;
|
|
|
|
-- Mnemonic CPL_F -------------------------------------------------------
|
|
when "10010101" | -- CPL F0
|
|
"10110101" => -- CPL F1
|
|
mnemonic_o <= MN_CPL_F;
|
|
|
|
-- Mnemonic DA ----------------------------------------------------------
|
|
when "01010111" => -- DA D
|
|
mnemonic_o <= MN_DA;
|
|
|
|
-- Mnemonic DEC ---------------------------------------------------------
|
|
when "11001000" | "11001001" | "11001010" | "11001011" | -- DEC Rr
|
|
"11001100" | "11001101" | "11001110" | "11001111" | --
|
|
"00000111" => -- DEC A
|
|
mnemonic_o <= MN_DEC;
|
|
|
|
-- Mnemonic DIS_EN_I ----------------------------------------------------
|
|
when "00010101" | -- DIS I
|
|
"00000101" => -- EN I
|
|
mnemonic_o <= MN_DIS_EN_I;
|
|
|
|
-- Mnemonic DIS_EN_TCNTI ------------------------------------------------
|
|
when "00110101" | -- DIS TCNTI
|
|
"00100101" => -- EN TCNTI
|
|
mnemonic_o <= MN_DIS_EN_TCNTI;
|
|
|
|
-- Mnemonic DJNZ --------------------------------------------------------
|
|
when "11101000" | "11101001" | "11101010" | "11101011" | -- DJNZ Rr, addr
|
|
"11101100" | "11101101" | "11101110" | "11101111" => --
|
|
mnemonic_o <= MN_DJNZ;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic ENT0_CLK ----------------------------------------------------
|
|
when "01110101" => -- ENT0 CLK
|
|
mnemonic_o <= MN_ENT0_CLK;
|
|
|
|
-- Mnemonic IN ----------------------------------------------------------
|
|
when "00001001" | "00001010" => -- IN A, Pp
|
|
mnemonic_o <= MN_IN;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic INC ---------------------------------------------------------
|
|
when "00010111" | -- INC A
|
|
"00011000" | "00011001" | "00011010" | "00011011" | -- INC Rr
|
|
"00011100" | "00011101" | "00011110" | "00011111" | --
|
|
"00010000" | "00010001" => -- INC @ Rr
|
|
mnemonic_o <= MN_INC;
|
|
|
|
-- Mnemonic INS ---------------------------------------------------------
|
|
when "00001000" => -- INS A, BUS
|
|
mnemonic_o <= MN_INS;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JBB ---------------------------------------------------------
|
|
when "00010010" | "00110010" | "01010010" | "01110010" | -- JBb addr
|
|
"10010010" | "10110010" | "11010010" | "11110010" => --
|
|
mnemonic_o <= MN_JBB;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JC ----------------------------------------------------------
|
|
when "11110110" | -- JC addr
|
|
"11100110" => -- JNC addr
|
|
mnemonic_o <= MN_JC;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JF ----------------------------------------------------------
|
|
when "10110110" | -- JF0 addr
|
|
"01110110" => -- JF1 addr
|
|
mnemonic_o <= MN_JF;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JMP ---------------------------------------------------------
|
|
when "00000100" | "00100100" | "01000100" | "01100100" | -- JMP addr
|
|
"10000100" | "10100100" | "11000100" | "11100100" => --
|
|
mnemonic_o <= MN_JMP;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JMPP --------------------------------------------------------
|
|
when "10110011" => -- JMPP @ A
|
|
mnemonic_o <= MN_JMPP;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JNI ---------------------------------------------------------
|
|
when "10000110" => -- JNI addr
|
|
mnemonic_o <= MN_JNI;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JT ----------------------------------------------------------
|
|
when "00100110" | -- JNT0 addr
|
|
"01000110" | -- JNT1 addr
|
|
"00110110" | -- JT0 addr
|
|
"01010110" => -- JT1 addr
|
|
mnemonic_o <= MN_JT;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JTF ---------------------------------------------------------
|
|
when "00010110" => -- JTF addr
|
|
mnemonic_o <= MN_JTF;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic JZ ----------------------------------------------------------
|
|
when "10010110" | -- JNZ addr
|
|
"11000110" => -- JZ addr
|
|
mnemonic_o <= MN_JZ;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic MOV_A_DATA --------------------------------------------------
|
|
when "00100011" => -- MOV A, data
|
|
mnemonic_o <= MN_MOV_A_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic MOV_A_PSW ---------------------------------------------------
|
|
when "11000111" => -- MOV A, PSW
|
|
mnemonic_o <= MN_MOV_A_PSW;
|
|
|
|
-- Mnemonic MOV_A_RR ----------------------------------------------------
|
|
when "11111000" | "11111001" | "11111010" | "11111011" | -- MOV A, Rr
|
|
"11111100" | "11111101" | "11111110" | "11111111" | --
|
|
"11110000" | "11110001" => -- MOV A, @ Rr
|
|
mnemonic_o <= MN_MOV_A_RR;
|
|
|
|
-- Mnemonic MOV_PSW_A ---------------------------------------------------
|
|
when "11010111" => -- MOV PSW, A
|
|
mnemonic_o <= MN_MOV_PSW_A;
|
|
|
|
-- Mnemonic MOV_RR ------------------------------------------------------
|
|
when "10101000" | "10101001" | "10101010" | "10101011" | -- MOV Rr, A
|
|
"10101100" | "10101101" | "10101110" | "10101111" | --
|
|
"10100000" | "10100001" => -- MOV @ Rr, A
|
|
mnemonic_o <= MN_MOV_RR;
|
|
|
|
-- Mnemonic MOV_RR_DATA -------------------------------------------------
|
|
when "10111000" | "10111001" | "10111010" | "10111011" | -- MOV Rr, data
|
|
"10111100" | "10111101" | "10111110" | "10111111" | --
|
|
"10110000" | "10110001" => -- MOV @ Rr, data
|
|
mnemonic_o <= MN_MOV_RR_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic MOV_T -------------------------------------------------------
|
|
when "01100010" | -- MOV T, A
|
|
"01000010" => -- MOV A, T
|
|
mnemonic_o <= MN_MOV_T;
|
|
|
|
-- Mnemonic MOVD_A_PP ---------------------------------------------------
|
|
when "00001100" | "00001101" | "00001110" | "00001111" => -- MOVD A, Pp
|
|
mnemonic_o <= MN_MOVD_A_PP;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic MOVP --------------------------------------------------------
|
|
when "10100011" | -- MOVP A, @ A
|
|
"11100011" => -- MOVP3 A, @ A
|
|
mnemonic_o <= MN_MOVP;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic MOVX --------------------------------------------------------
|
|
when "10000000" | "10000001" | -- MOVX A, @ Rr
|
|
"10010000" | "10010001" => -- MOVX @ Rr, A
|
|
mnemonic_o <= MN_MOVX;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic NOP ---------------------------------------------------------
|
|
when "00000000" => -- NOP
|
|
mnemonic_o <= MN_NOP;
|
|
|
|
-- Mnemonic ORL ---------------------------------------------------------
|
|
when "01001000" | "01001001" | "01001010" | "01001011" | -- ORL A, Rr
|
|
"01001100" | "01001101" | "01001110" | "01001111" | --
|
|
"01000000" | "01000001" => -- ORL A, @ Rr
|
|
mnemonic_o <= MN_ORL;
|
|
|
|
-- Mnemonic ORL_A_DATA --------------------------------------------------
|
|
when "01000011" => -- ORL A, data
|
|
mnemonic_o <= MN_ORL_A_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic ORL_EXT -----------------------------------------------------
|
|
when "10001000" | -- ORL BUS, data
|
|
"10001001" | "10001010" => -- ORL Pp, data
|
|
mnemonic_o <= MN_ORL_EXT;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic OUTD_PP_A ---------------------------------------------------
|
|
when "00111100" | "00111101" | "00111110" | "00111111" | -- MOVD Pp, A
|
|
"10011100" | "10011101" | "10011110" | "10011111" | -- ANLD PP, A
|
|
"10001100" | "10001101" | "10001110" | "10001111" => -- ORLD Pp, A
|
|
mnemonic_o <= MN_OUTD_PP_A;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic OUTL_EXT ----------------------------------------------------
|
|
when "00111001" | "00111010" | -- OUTL Pp, A
|
|
"00000010" => -- OUTL BUS, A
|
|
mnemonic_o <= MN_OUTL_EXT;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic RET ---------------------------------------------------------
|
|
when "10000011" | -- RET
|
|
"10010011" => -- RETR
|
|
mnemonic_o <= MN_RET;
|
|
multi_cycle_o <= '1';
|
|
|
|
-- Mnemonic RL ----------------------------------------------------------
|
|
when "11100111" | -- RL A
|
|
"11110111" => -- RLC A
|
|
mnemonic_o <= MN_RL;
|
|
|
|
-- Mnemonic RR ----------------------------------------------------------
|
|
when "01110111" | -- RR A
|
|
"01100111" => -- RRC A
|
|
mnemonic_o <= MN_RR;
|
|
|
|
-- Mnemonic SEL_MB ------------------------------------------------------
|
|
when "11100101" | -- SEL MB0
|
|
"11110101" => -- SEL MB1
|
|
mnemonic_o <= MN_SEL_MB;
|
|
|
|
-- Mnemonic SEL_RB ------------------------------------------------------
|
|
when "11000101" | -- SEL RB0
|
|
"11010101" => -- SEL RB1
|
|
mnemonic_o <= MN_SEL_RB;
|
|
|
|
-- Mnemonic STOP_TCNT ---------------------------------------------------
|
|
when "01100101" => -- STOP TCNT
|
|
mnemonic_o <= MN_STOP_TCNT;
|
|
|
|
-- Mnemonic START -------------------------------------------------------
|
|
when "01000101" | -- STRT CNT
|
|
"01010101" => -- STRT T
|
|
mnemonic_o <= MN_STRT;
|
|
|
|
-- Mnemonic SWAP --------------------------------------------------------
|
|
when "01000111" => -- SWAP A
|
|
mnemonic_o <= MN_SWAP;
|
|
|
|
-- Mnemonic XCH ---------------------------------------------------------
|
|
when "00101000" | "00101001" | "00101010" | "00101011" | -- XCH A, Rr
|
|
"00101100" | "00101101" | "00101110" | "00101111" | --
|
|
"00100000" | "00100001" | -- XCH A, @ Rr
|
|
"00110000" | "00110001" => -- XCHD A, @ Rr
|
|
mnemonic_o <= MN_XCH;
|
|
|
|
-- Mnemonic XRL ---------------------------------------------------------
|
|
when "11011000" | "11011001" | "11011010" | "11011011" | -- XRL A, Rr
|
|
"11011100" | "11011101" | "11011110" | "11011111" | --
|
|
"11010000" | "11010001" => -- XRL A, @ Rr
|
|
mnemonic_o <= MN_XRL;
|
|
|
|
-- Mnemonic XRL_A_DATA --------------------------------------------------
|
|
when "11010011" => -- XRL A, data
|
|
mnemonic_o <= MN_XRL_A_DATA;
|
|
multi_cycle_o <= '1';
|
|
|
|
when others =>
|
|
-- pragma translate_off
|
|
assert now = 0 ns
|
|
report "Unknown opcode."
|
|
severity warning;
|
|
-- pragma translate_on
|
|
|
|
end case;
|
|
|
|
end process opc_decode;
|
|
--
|
|
-----------------------------------------------------------------------------
|
|
|
|
end rtl;
|
|
|
|
|
|
-------------------------------------------------------------------------------
|
|
-- File History:
|
|
--
|
|
-- $Log: opc_table.vhd,v $
|
|
-- Revision 1.3 2004/07/11 16:51:33 arniml
|
|
-- cleanup copyright notice
|
|
--
|
|
-- Revision 1.2 2004/03/28 13:10:48 arniml
|
|
-- merge MN_ANLD, MN_MOVD_PP_A and MN_ORLD_PP_A to OUTLD_PP_A
|
|
--
|
|
-- Revision 1.1 2004/03/23 21:31:52 arniml
|
|
-- initial check-in
|
|
--
|
|
-------------------------------------------------------------------------------
|