URL
https://opencores.org/ocsvn/cpu65c02_true_cycle/cpu65c02_true_cycle/trunk
Subversion Repositories cpu65c02_true_cycle
[/] [cpu65c02_true_cycle/] [trunk/] [released/] [rtl/] [v2_00/] [vhdl/] [reg_pc.vhd] - Rev 24
Compare with Previous | Blame | View Log
LIBRARY ieee; USE ieee.std_logic_1164.all; USE ieee.std_logic_arith.all; entity reg_pc is port( adr_i : in std_logic_vector (15 downto 0); clk_clk_i : in std_logic; ld_i : in std_logic_vector (1 downto 0); ld_pc_i : in std_logic; offset_i : in std_logic_vector (15 downto 0); rst_rst_n_i : in std_logic; sel_pc_in_i : in std_logic; sel_pc_val_i : in std_logic_vector (1 downto 0); adr_nxt_pc_o : out std_logic_vector (15 downto 0); adr_pc_o : out std_logic_vector (15 downto 0) ); -- Declarations end reg_pc ; -- (C) 2008 - 2021 Jens Gutschmidt -- (email: opencores@vivare-services.com) -- -- Versions: -- Revision 1.8 2021/01/10 17:40:00 jens -- - Performance improvements -- -- Revision 1.7 2013/07/21 11:11:00 jens -- - Changing the title block and internal revision history -- -- Revision 1.6 2009/01/04 10:20:47 eda -- Changes for cosmetic issues only -- -- Revision 1.5 2009/01/04 09:23:10 eda -- - Delete unused nets and blocks (same as R6502_TC) -- - Rename blocks -- -- Revision 1.4 2009/01/03 16:53:02 eda -- - Unused nets and blocks deleted -- - Renamed blocks -- -- Revision 1.3 2009/01/03 16:42:02 eda -- - Unused nets and blocks deleted -- - Renamed blocks -- -- Revision 1.2 2008/12/31 19:31:24 eda -- Production Release -- -- -- -- r65c02_tc.reg_pc.struct -- -- Date: 14.01.2021 -- Time: 16:34:05 -- By: VIVARE GmbH, Switzerland -- -- COPYRIGHT (C) 2008 - 2021 by Jens Gutschmidt -- -- This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version. -- -- This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. -- -- You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. -- -- LIBRARY ieee; USE ieee.std_logic_1164.all; USE ieee.std_logic_arith.all; architecture struct of reg_pc is -- Architecture declarations -- Internal signal declarations signal adr_pc_high_o_i : std_logic_vector(7 downto 0); signal adr_pc_low_o_i : std_logic_vector(7 downto 0); signal adr_pc_o_i : std_logic_vector(15 downto 0); signal cout_pc_o_i : std_logic; signal load3_o_i : std_logic; signal load_o_i : std_logic; signal offset_high_o_i : std_logic_vector(7 downto 0); signal offset_low_o_i : std_logic_vector(7 downto 0); signal val_o_i : std_logic_vector(7 downto 0); signal val_one : std_logic_vector(7 downto 0); signal val_zero : std_logic_vector(7 downto 0); -- Implicit buffer signal declarations signal adr_nxt_pc_o_internal : std_logic_vector (15 downto 0); signal adr_pc_o_internal : std_logic_vector (15 downto 0); -- ModuleWare signal declarations(v1.12) for instance 'U_0' of 'adff' signal mw_U_0reg_cval : std_logic_vector(7 downto 0); -- ModuleWare signal declarations(v1.12) for instance 'U_4' of 'adff' signal mw_U_4reg_cval : std_logic_vector(15 downto 8); -- ModuleWare signal declarations(v1.12) for instance 'U_3' of 'split' signal mw_U_3temp_din : std_logic_vector(15 downto 0); -- ModuleWare signal declarations(v1.12) for instance 'U_5' of 'split' signal mw_U_5temp_din : std_logic_vector(15 downto 0); begin -- ModuleWare code(v1.12) for instance 'U_2' of 'add' u_2combo_proc: process (adr_pc_low_o_i, val_o_i) variable temp_din0 : std_logic_vector(8 downto 0); variable temp_din1 : std_logic_vector(8 downto 0); variable temp_sum : unsigned(8 downto 0); variable temp_carry : std_logic; begin temp_din0 := '0' & adr_pc_low_o_i; temp_din1 := '0' & val_o_i; temp_carry := '0'; temp_sum := unsigned(temp_din0) + unsigned(temp_din1) + temp_carry; adr_nxt_pc_o_internal(7 DOWNTO 0) <= conv_std_logic_vector(temp_sum(7 downto 0),8); cout_pc_o_i <= temp_sum(8) ; end process u_2combo_proc; -- ModuleWare code(v1.12) for instance 'U_11' of 'add' u_11combo_proc: process (adr_pc_high_o_i, offset_high_o_i, cout_pc_o_i) variable temp_din0 : std_logic_vector(8 downto 0); variable temp_din1 : std_logic_vector(8 downto 0); variable temp_sum : unsigned(8 downto 0); variable temp_carry : std_logic; begin temp_din0 := '0' & adr_pc_high_o_i; temp_din1 := '0' & offset_high_o_i; temp_carry := cout_pc_o_i; temp_sum := unsigned(temp_din0) + unsigned(temp_din1) + temp_carry; adr_nxt_pc_o_internal(15 DOWNTO 8) <= conv_std_logic_vector(temp_sum(7 downto 0),8); end process u_11combo_proc; -- ModuleWare code(v1.12) for instance 'U_0' of 'adff' adr_pc_o_internal(7 DOWNTO 0) <= mw_U_0reg_cval; u_0seq_proc: process (clk_clk_i, rst_rst_n_i) begin if (rst_rst_n_i = '0') then mw_U_0reg_cval <= "00000000"; elsif (clk_clk_i'event and clk_clk_i='1') then if (load_o_i = '1') then mw_U_0reg_cval <= adr_nxt_pc_o_internal(7 DOWNTO 0); end if; end if; end process u_0seq_proc; -- ModuleWare code(v1.12) for instance 'U_4' of 'adff' adr_pc_o_internal(15 DOWNTO 8) <= mw_U_4reg_cval; u_4seq_proc: process (clk_clk_i, rst_rst_n_i) begin if (rst_rst_n_i = '0') then mw_U_4reg_cval <= "00000000"; elsif (clk_clk_i'event and clk_clk_i='1') then if (load3_o_i = '1') then mw_U_4reg_cval <= adr_nxt_pc_o_internal(15 DOWNTO 8); end if; end if; end process u_4seq_proc; -- ModuleWare code(v1.12) for instance 'U_6' of 'and' load_o_i <= ld_pc_i and ld_i(0); -- ModuleWare code(v1.12) for instance 'U_7' of 'and' load3_o_i <= ld_pc_i and ld_i(1); -- ModuleWare code(v1.12) for instance 'U_1' of 'constval' val_zero <= "00000000"; -- ModuleWare code(v1.12) for instance 'U_9' of 'constval' val_one <= "00000001"; -- ModuleWare code(v1.12) for instance 'U_8' of 'mux' u_8combo_proc: process(adr_pc_o_internal, adr_i, sel_pc_in_i) begin case sel_pc_in_i is when '0' => adr_pc_o_i <= adr_pc_o_internal; when '1' => adr_pc_o_i <= adr_i; when others => adr_pc_o_i <= (others => 'X'); end case; end process u_8combo_proc; -- ModuleWare code(v1.12) for instance 'U_13' of 'mux' u_13combo_proc: process(val_one, val_zero, offset_low_o_i, sel_pc_val_i) begin case sel_pc_val_i is when "00" => val_o_i <= val_one; when "01" => val_o_i <= val_zero; when "10" => val_o_i <= offset_low_o_i; when "11" => val_o_i <= val_zero; when others => val_o_i <= (others => 'X'); end case; end process u_13combo_proc; -- ModuleWare code(v1.12) for instance 'U_3' of 'split' mw_U_3temp_din <= adr_pc_o_i; u_3combo_proc: process (mw_U_3temp_din) variable temp_din: std_logic_vector(15 downto 0); begin temp_din := mw_U_3temp_din(15 downto 0); adr_pc_low_o_i <= temp_din(7 downto 0); adr_pc_high_o_i <= temp_din(15 downto 8); end process u_3combo_proc; -- ModuleWare code(v1.12) for instance 'U_5' of 'split' mw_U_5temp_din <= offset_i; u_5combo_proc: process (mw_U_5temp_din) variable temp_din: std_logic_vector(15 downto 0); begin temp_din := mw_U_5temp_din(15 downto 0); offset_low_o_i <= temp_din(7 downto 0); offset_high_o_i <= temp_din(15 downto 8); end process u_5combo_proc; -- Instance port mappings. -- Implicit buffered output assignments adr_nxt_pc_o <= adr_nxt_pc_o_internal; adr_pc_o <= adr_pc_o_internal; end struct;