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[/] [psg16/] [trunk/] [rtl/] [verilog/] [PSG16.v] - Blame information for rev 2

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`timescale 1ns / 1ps
//=============================================================================
//      (C) 2007,2010,2012  Robert Finch
//      robfinch<remove>@opencores.org
//
//      PSG16.v 
//              4 Channel ADSR sound generator
//
// This source file is free software: you can redistribute it and/or modify 
// it under the terms of the GNU Lesser General Public License as published 
// by the Free Software Foundation, either version 3 of the License, or     
// (at your option) any later version.                                      
//                                                                          
// This source file 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/>.    
//
//
//      Registers
//      0            ffffffff ffffffff   freq [15:0]
//      1           ----pppp pppppppp   pulse width [11:0]
//      2           trsg--fo -vvvvv--   test, ringmod, sync, gate, filter, output, voice type
//                                                                                      vvvvv
//                                                                                      wnpst
//      3           ssssrrrr aaaadddd   sustain,release,attack,decay
//
//      ...
//      64      -------- ----vvvv   volume (0-15)
//      65      nnnnnnnn nnnnnnnn   osc3 oscillator 3
//      66      -------- nnnnnnnn   env3 envelope 3
//      67
//      68      aa------ --------   wave table address a15-14
//      69      aaaaaaaa aaaaaaaa   wave table address a31-16
//
//  80-87   s---kkkk kkkkkkkk   filter coefficients
//  88-96   -------- --------   reserved for more filter coefficients
//
//
//      Spartan3
//      Webpack 12.3  xc3s1200e-4fg320
//      1290 LUTs / 893 slices / 69.339 MHz
//      1 Multipliers
//=============================================================================
 
module PSG16(rst_i, clk_i, cyc_i, stb_i, ack_o, we_i, sel_i, adr_i, dat_i, dat_o,
        vol_o, bg,
        m_cyc_o, m_stb_o, m_ack_i, m_we_o, m_sel_o, m_adr_o, m_dat_i, o
);
parameter pClkDivide = 66;
 
// WISHBONE SYSCON
input rst_i;
input clk_i;                    // system clock
// WISHBONE SLAVE
input cyc_i;                    // cycle valid
input stb_i;                    // circuit select
output ack_o;
input we_i;                             // write
input  [1:0] sel_i;              // byte selects
input [63:0] adr_i;              // address input
input [15:0] dat_i;              // data input
output [15:0] dat_o;     // data output
// WISHBONE MASTER
output m_cyc_o;                 // bus request
output m_stb_o;                 // strobe output
input m_ack_i;
output m_we_o;                  // write enable (always inactive)
output [ 1:0] m_sel_o;   // byte lane selects
output [63:0] m_adr_o;   // wave table address
input  [11:0] m_dat_i;   // wave table data input
 
output vol_o;
 
input bg;                               // bus grant
 
output [17:0] o;
 
// I/O registers
reg [15:0] dat_o;
reg vol_o;
reg [43:0] m_adr_o;
 
reg [3:0] test;                          // test (enable note generator)
reg [4:0] vt [3:0];                       // voice type
reg [15:0] freq0, freq1, freq2, freq3;   // frequency control
reg [11:0] pw0, pw1, pw2, pw3;                   // pulse width control
reg [3:0] gate;
reg [3:0] attack0, attack1, attack2, attack3;
reg [3:0] decay0, decay1, decay2, decay3;
reg [3:0] sustain0, sustain1, sustain2, sustain3;
reg [3:0] relese0, relese1, relese2, relese3;
reg [3:0] sync;
reg [3:0] ringmod;
reg [3:0] outctrl;
reg [3:0] filt;                // 1 = output goes to filter
wire [23:0] acc0, acc1, acc2, acc3;
reg [3:0] volume;        // master volume
wire [11:0] ngo; // not generator output
wire [7:0] env;          // envelope generator output
wire [7:0] env3;
wire [7:0] ibr;
wire [7:0] ibg;
wire [21:0] out1;
reg [21:0] out1a;
wire [19:0] out2;
wire [21:0] out3;
wire [19:0] out4;
wire [21:0] filtin1;     // FIR filter input
wire [14:0] filt_o;              // FIR filter output
 
wire cs = cyc_i && stb_i && (adr_i[63:8]==56'hFFFF_FFFF_FFD5_00);
assign m_cyc_o = |ibg & !m_ack_i;
assign m_stb_o = m_cyc_o;
assign m_we_o  = 1'b0;
assign m_sel_o = {m_cyc_o,m_cyc_o};
reg ack1;
always @(posedge clk_i)
        ack1 <= cs & !ack1;
assign ack_o = cs ? (we_i ? 1'b1 : ack1) : 1'b0;
wire my_ack = m_ack_i;
 
// write to registers
always @(posedge clk_i)
begin
        if (rst_i) begin
                freq0 <= 0;
                freq1 <= 0;
                freq2 <= 0;
                freq3 <= 0;
                pw0 <= 0;
                pw1 <= 0;
                pw2 <= 0;
                pw3 <= 0;
                test <= 0;
                vt[0] <= 0;
                vt[1] <= 0;
                vt[2] <= 0;
                vt[3] <= 0;
                gate <= 0;
                outctrl <= 0;
                filt <= 0;
                attack0 <= 0;
                attack1 <= 0;
                attack2 <= 0;
                attack3 <= 0;
                decay0 <= 0;
                sustain0 <= 0;
                relese0 <= 0;
                decay1 <= 0;
                sustain1 <= 0;
                relese1 <= 0;
                decay2 <= 0;
                sustain2 <= 0;
                relese2 <= 0;
                decay3 <= 0;
                sustain3 <= 0;
                relese3 <= 0;
                sync <= 0;
                ringmod <= 0;
                volume <= 0;
                m_adr_o[47:14] <= 34'b00000000_00000000_0000_0000_0000_0011_10; // 00038000
        end
        else begin
                if (cs & we_i) begin
                        case(adr_i[7:1])
                        //---------------------------------------------------------
                        7'd0:
                                        begin
                                                if (sel_i[0]) freq0[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) freq0[15:8] <= dat_i[15:8];
                                        end
                        7'd1:
                                        begin
                                                if (sel_i[0]) pw0[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) pw0[11:8] <= dat_i[11:8];
                                        end
                        7'd2:   begin
                                                if (sel_i[0]) vt[0] <= dat_i[6:2];
                                                if (sel_i[1]) begin
                                                        outctrl[0] <= dat_i[8];
                                                        filt[0] <= dat_i[9];
                                                        gate[0] <= dat_i[12];
                                                        sync[0] <= dat_i[13];
                                                        ringmod[0] <= dat_i[14];
                                                        test[0] <= dat_i[15];
                                                end
                                        end
                        7'd3:   begin
                                        if (sel_i[0]) attack0 <= dat_i[7:4];
                                        if (sel_i[0]) decay0 <= dat_i[3:0];
                                        if (sel_i[1]) relese0 <= dat_i[11:8];
                                        if (sel_i[1]) sustain0 <= dat_i[15:12];
                                        end
 
                        //---------------------------------------------------------
                        7'd4:
                                        begin
                                                if (sel_i[0]) freq1[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) freq1[15:8] <= dat_i[15:8];
                                        end
                        7'd5:
                                        begin
                                                if (sel_i[0]) pw1[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) pw1[11:8] <= dat_i[11:8];
                                        end
                        7'd6:   begin
                                                if (sel_i[0]) vt[1] <= dat_i[6:2];
                                                if (sel_i[1]) begin
                                                        outctrl[1] <= dat_i[8];
                                                        filt[1] <= dat_i[9];
                                                        gate[1] <= dat_i[12];
                                                        sync[1] <= dat_i[13];
                                                        ringmod[1] <= dat_i[14];
                                                        test[1] <= dat_i[15];
                                                end
                                        end
                        7'd7:   begin
                                        if (sel_i[0]) attack1 <= dat_i[7:4];
                                        if (sel_i[0]) decay1 <= dat_i[3:0];
                                        if (sel_i[1]) relese1 <= dat_i[11:8];
                                        if (sel_i[1]) sustain1 <= dat_i[15:12];
                                        end
 
                        //---------------------------------------------------------
                        7'd8:
                                        begin
                                                if (sel_i[0]) freq2[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) freq2[15:8] <= dat_i[15:8];
                                        end
                        7'd9:
                                        begin
                                                if (sel_i[0]) pw2[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) pw2[11:8] <= dat_i[11:8];
                                        end
                        7'd10:  begin
                                                if (sel_i[0]) vt[2] <= dat_i[6:2];
                                                if (sel_i[1]) begin
                                                        outctrl[2] <= dat_i[8];
                                                        filt[2] <= dat_i[9];
                                                        gate[2] <= dat_i[12];
                                                        sync[2] <= dat_i[5];
                                                        outctrl[0] <= dat_i[13];
                                                        ringmod[2] <= dat_i[14];
                                                        test[2] <= dat_i[15];
                                                end
                                        end
                        7'd11:  begin
                                        if (sel_i[0]) attack2 <= dat_i[7:4];
                                        if (sel_i[0]) decay2 <= dat_i[3:0];
                                        if (sel_i[1]) relese2 <= dat_i[11:8];
                                        if (sel_i[1]) sustain2 <= dat_i[15:12];
                                        end
 
                        //---------------------------------------------------------
                        7'd12:
                                        begin
                                                if (sel_i[0]) freq3[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) freq3[15:8] <= dat_i[15:8];
                                        end
                        7'd13:
                                        begin
                                                if (sel_i[0]) pw3[ 7:0] <= dat_i[ 7:0];
                                                if (sel_i[1]) pw3[11:8] <= dat_i[11:8];
                                        end
                        7'd14:  begin
                                                if (sel_i[0]) vt[3] <= dat_i[6:2];
                                                if (sel_i[1]) begin
                                                        outctrl[3] <= dat_i[8];
                                                        filt[3] <= dat_i[9];
                                                        gate[3] <= dat_i[12];
                                                        sync[3] <= dat_i[13];
                                                        ringmod[3] <= dat_i[14];
                                                        test[3] <= dat_i[15];
                                                end
                                        end
                        7'd15:  begin
                                        if (sel_i[0]) attack3 <= dat_i[7:4];
                                        if (sel_i[0]) decay3 <= dat_i[3:0];
                                        if (sel_i[1]) relese3 <= dat_i[11:8];
                                        if (sel_i[1]) sustain3 <= dat_i[15:12];
                                        end
 
                        //---------------------------------------------------------
                        7'd64:  if (sel_i[0]) volume <= dat_i[3:0];
 
                        7'd68:  begin
                                                if (sel_i[1]) m_adr_o[15:14] <= dat_i[15:14];
                                        end
                        7'd69:
                                        begin
                                                if (sel_i[0]) m_adr_o[23:16] <= dat_i[ 7:0];
                                                if (sel_i[1]) m_adr_o[31:24] <= dat_i[15:8];
                                        end
                        7'd70:  begin
                                                if (sel_i[0]) m_adr_o[39:32] <= dat_i[ 7:0];
                                                if (sel_i[1]) m_adr_o[47:40] <= dat_i[15:8];
                                        end
                        default:        ;
                        endcase
                end
        end
end
 
 
always @(posedge clk_i)
        if (cs) begin
                case(adr_i[6:0])
                7'd65:  begin
                                vol_o <= 1'b1;
                                dat_o <= acc3[23:8];
                                end
                7'd66:  begin
                                vol_o <= 1'b1;
                                dat_o <= env3;
                                end
                default: begin
                                dat_o <= env3;
                                vol_o <= 1'b0;
                                end
                endcase
        end
        else begin
                dat_o <= 16'b0;
                vol_o <= 1'b0;
        end
 
wire [11:0] alow;
 
// set wave table output address
always @(ibg or acc1 or acc0 or acc2 or acc3 or alow)
begin
        m_adr_o[13:12] <= {ibg[2]|ibg[3],ibg[1]|ibg[3]};
        m_adr_o[11:0] <= alow;
end
 
mux4to1 #(12) u11
(
        .e(1'b1),
        .s(m_adr_o[13:12]),
        .i0({acc0[23:13],1'b0}),
        .i1({acc1[23:13],1'b0}),
        .i2({acc2[23:13],1'b0}),
        .i3({acc3[23:13],1'b0}),
        .z(alow)
);
 
// This counter controls channel multiplexing and the base
// operating frequency.
wire [7:0] cnt;
reg [7:0] cnt1,cnt2,cnt3;
counter #(8) u1
(
        .rst(rst_i),
        .clk(clk_i),
        .ce(1'b1),
        .ld(cnt==pClkDivide-1),
        .d(8'd0),
        .q(cnt)
);
 
// channel select signal
wire [1:0] sel = cnt[1:0];
 
 
// bus arbitrator for wave table access
wire [2:0] bgn;
PSGBusArb u2
(
        .rst(rst_i),
        .clk(clk_i),
        .ce(1'b1),
        .ack(1'b1),
        .seln(bgn),
        .req0(ibr[0]),
        .req1(ibr[1]),
        .req2(ibr[2]),
        .req3(ibr[3]),
        .req4(1'b0),
        .req5(1'b0),
        .req6(1'b0),
        .req7(1'b0),
        .sel0(ibg[0]),
        .sel1(ibg[1]),
        .sel2(ibg[2]),
        .sel3(ibg[3]),
        .sel4(),
        .sel5(),
        .sel6(),
        .sel7()
);
 
// note generator - multi-channel
PSGNoteGen u3
(
        .rst(rst_i),
        .clk(clk_i),
        .cnt(cnt),
        .br(ibr),
        .bg(ibg),
        .ack(m_ack_i),
        .bgn(bgn),
        .test(test),
        .vt0(vt[0]),
        .vt1(vt[1]),
        .vt2(vt[2]),
        .vt3(vt[3]),
        .freq0(freq0),
        .freq1(freq1),
        .freq2(freq2),
        .freq3(freq3),
        .pw0(pw0),
        .pw1(pw1),
        .pw2(pw2),
        .pw3(pw3),
        .acc0(acc0),
        .acc1(acc1),
        .acc2(acc2),
        .acc3(acc3),
        .wave(m_dat_i),
        .sync(sync),
        .ringmod(ringmod),
        .o(ngo)
);
 
// envelope generator - multi-channel
PSGEnvGen u4
(
        .rst(rst_i),
        .clk(clk_i),
        .cnt(cnt),
        .gate(gate),
        .attack0(attack0),
        .attack1(attack1),
        .attack2(attack2),
        .attack3(attack3),
        .decay0(decay0),
        .decay1(decay1),
        .decay2(decay2),
        .decay3(decay3),
        .sustain0(sustain0),
        .sustain1(sustain1),
        .sustain2(sustain2),
        .sustain3(sustain3),
        .relese0(relese0),
        .relese1(relese1),
        .relese2(relese2),
        .relese3(relese3),
        .o(env)
);
 
// shape output according to envelope
PSGShaper u5
(
        .clk_i(clk_i),
        .ce(1'b1),
        .tgi(ngo),
        .env(env),
        .o(out2)
);
 
always @(posedge clk_i)
        cnt1 <= cnt;
always @(posedge clk_i)
        cnt2 <= cnt1;
always @(posedge clk_i)
        cnt3 <= cnt2;
 
// Sum the channels not going to the filter
PSGChannelSummer u6
(
        .clk_i(clk_i),
        .cnt(cnt1),
        .outctrl(outctrl),
        .tmc_i(out2),
        .o(out1)
);
 
always @(posedge clk_i)
        out1a <= out1;
 
// Sum the channels going to the filter
PSGChannelSummer u7
(
        .clk_i(clk_i),
        .cnt(cnt1),
        .outctrl(filt),
        .tmc_i(out2),
        .o(filtin1)
);
 
// The FIR filter
PSGFilter u8
(
        .rst(rst_i),
        .clk(clk_i),
        .cnt(cnt2),
        .wr(we_i && stb_i && adr_i[6:4]==3'b101),
    .adr(adr_i[3:0]),
    .din({dat_i[15],dat_i[11:0]}),
    .i(filtin1[21:7]),
    .o(filt_o)
);
 
// Sum the filtered and unfiltered output
PSGOutputSummer u9
(
        .clk_i(clk_i),
        .cnt(cnt3),
        .ufi(out1a),
        .fi({filt_o,7'b0}),
        .o(out3)
);
 
// Last stage:
// Adjust output according to master volume
PSGMasterVolumeControl u10
(
        .rst_i(rst_i),
        .clk_i(clk_i),
        .i(out3[21:6]),
        .volume(volume),
        .o(out4)
);
 
assign o = out4[19:2];
 
endmodule
 

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[/] [psg16/] [trunk/] [rtl/] [verilog/] [PSG16.v] - Blame information for rev 2

Line No.	Rev	Author	Line
1	2	robfinch	`timescale 1ns / 1ps
2			`//=============================================================================`
3			`// (C) 2007,2010,2012 Robert Finch`
4			`// robfinch<remove>@opencores.org`
5			`//`
6			`// PSG16.v`
7			`// 4 Channel ADSR sound generator`
8			`//`
9			`// This source file is free software: you can redistribute it and/or modify`
10			`// it under the terms of the GNU Lesser General Public License as published`
11			`// by the Free Software Foundation, either version 3 of the License, or`
12			`// (at your option) any later version.`
13			`//`
14			`// This source file is distributed in the hope that it will be useful,`
15			`// but WITHOUT ANY WARRANTY; without even the implied warranty of`
16			`// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the`
17			`// GNU General Public License for more details.`
18			`//`
19			`// You should have received a copy of the GNU General Public License`
20			`// along with this program. If not, see <http://www.gnu.org/licenses/>.`
21			`//`
22			`//`
23			`// Registers`
24			`// 0 ffffffff ffffffff freq [15:0]`
25			`// 1 ----pppp pppppppp pulse width [11:0]`
26			`// 2 trsg--fo -vvvvv-- test, ringmod, sync, gate, filter, output, voice type`
27			`// vvvvv`
28			`// wnpst`
29			`// 3 ssssrrrr aaaadddd sustain,release,attack,decay`
30			`//`
31			`// ...`
32			`// 64 -------- ----vvvv volume (0-15)`
33			`// 65 nnnnnnnn nnnnnnnn osc3 oscillator 3`
34			`// 66 -------- nnnnnnnn env3 envelope 3`
35			`// 67`
36			`// 68 aa------ -------- wave table address a15-14`
37			`// 69 aaaaaaaa aaaaaaaa wave table address a31-16`
38			`//`
39			`// 80-87 s---kkkk kkkkkkkk filter coefficients`
40			`// 88-96 -------- -------- reserved for more filter coefficients`
41			`//`
42			`//`
43			`// Spartan3`
44			`// Webpack 12.3 xc3s1200e-4fg320`
45			`// 1290 LUTs / 893 slices / 69.339 MHz`
46			`// 1 Multipliers`
47			`//=============================================================================`
48
49			`module PSG16(rst_i, clk_i, cyc_i, stb_i, ack_o, we_i, sel_i, adr_i, dat_i, dat_o,`
50			`vol_o, bg,`
51			`m_cyc_o, m_stb_o, m_ack_i, m_we_o, m_sel_o, m_adr_o, m_dat_i, o`
52			`);`
53			`parameter pClkDivide = 66;`
54
55			`// WISHBONE SYSCON`
56			`input rst_i;`
57			`input clk_i; // system clock`
58			`// WISHBONE SLAVE`
59			`input cyc_i; // cycle valid`
60			`input stb_i; // circuit select`
61			`output ack_o;`
62			`input we_i; // write`
63			`input [1:0] sel_i; // byte selects`
64			`input [63:0] adr_i; // address input`
65			`input [15:0] dat_i; // data input`
66			`output [15:0] dat_o; // data output`
67			`// WISHBONE MASTER`
68			`output m_cyc_o; // bus request`
69			`output m_stb_o; // strobe output`
70			`input m_ack_i;`
71			`output m_we_o; // write enable (always inactive)`
72			`output [ 1:0] m_sel_o; // byte lane selects`
73			`output [63:0] m_adr_o; // wave table address`
74			`input [11:0] m_dat_i; // wave table data input`
75
76			`output vol_o;`
77
78			`input bg; // bus grant`
79
80			`output [17:0] o;`
81
82			`// I/O registers`
83			`reg [15:0] dat_o;`
84			`reg vol_o;`
85			`reg [43:0] m_adr_o;`
86
87			`reg [3:0] test; // test (enable note generator)`
88			`reg [4:0] vt [3:0]; // voice type`
89			`reg [15:0] freq0, freq1, freq2, freq3; // frequency control`
90			`reg [11:0] pw0, pw1, pw2, pw3; // pulse width control`
91			`reg [3:0] gate;`
92			`reg [3:0] attack0, attack1, attack2, attack3;`
93			`reg [3:0] decay0, decay1, decay2, decay3;`
94			`reg [3:0] sustain0, sustain1, sustain2, sustain3;`
95			`reg [3:0] relese0, relese1, relese2, relese3;`
96			`reg [3:0] sync;`
97			`reg [3:0] ringmod;`
98			`reg [3:0] outctrl;`
99			`reg [3:0] filt; // 1 = output goes to filter`
100			`wire [23:0] acc0, acc1, acc2, acc3;`
101			`reg [3:0] volume; // master volume`
102			`wire [11:0] ngo; // not generator output`
103			`wire [7:0] env; // envelope generator output`
104			`wire [7:0] env3;`
105			`wire [7:0] ibr;`
106			`wire [7:0] ibg;`
107			`wire [21:0] out1;`
108			`reg [21:0] out1a;`
109			`wire [19:0] out2;`
110			`wire [21:0] out3;`
111			`wire [19:0] out4;`
112			`wire [21:0] filtin1; // FIR filter input`
113			`wire [14:0] filt_o; // FIR filter output`
114
115			`wire cs = cyc_i && stb_i && (adr_i[63:8]==56'hFFFF_FFFF_FFD5_00);`
116			`assign m_cyc_o = \|ibg & !m_ack_i;`
117			`assign m_stb_o = m_cyc_o;`
118			`assign m_we_o = 1'b0;`
119			`assign m_sel_o = {m_cyc_o,m_cyc_o};`
120			`reg ack1;`
121			`always @(posedge clk_i)`
122			`ack1 <= cs & !ack1;`
123			`assign ack_o = cs ? (we_i ? 1'b1 : ack1) : 1'b0;`
124			`wire my_ack = m_ack_i;`
125
126			`// write to registers`
127			`always @(posedge clk_i)`
128			`begin`
129			`if (rst_i) begin`
130			`freq0 <= 0;`
131			`freq1 <= 0;`
132			`freq2 <= 0;`
133			`freq3 <= 0;`
134			`pw0 <= 0;`
135			`pw1 <= 0;`
136			`pw2 <= 0;`
137			`pw3 <= 0;`
138			`test <= 0;`
139			`vt[0] <= 0;`
140			`vt[1] <= 0;`
141			`vt[2] <= 0;`
142			`vt[3] <= 0;`
143			`gate <= 0;`
144			`outctrl <= 0;`
145			`filt <= 0;`
146			`attack0 <= 0;`
147			`attack1 <= 0;`
148			`attack2 <= 0;`
149			`attack3 <= 0;`
150			`decay0 <= 0;`
151			`sustain0 <= 0;`
152			`relese0 <= 0;`
153			`decay1 <= 0;`
154			`sustain1 <= 0;`
155			`relese1 <= 0;`
156			`decay2 <= 0;`
157			`sustain2 <= 0;`
158			`relese2 <= 0;`
159			`decay3 <= 0;`
160			`sustain3 <= 0;`
161			`relese3 <= 0;`
162			`sync <= 0;`
163			`ringmod <= 0;`
164			`volume <= 0;`
165			`m_adr_o[47:14] <= 34'b00000000_00000000_0000_0000_0000_0011_10; // 00038000`
166			`end`
167			`else begin`
168			`if (cs & we_i) begin`
169			`case(adr_i[7:1])`
170			`//---------------------------------------------------------`
171			`7'd0:`
172			`begin`
173			`if (sel_i[0]) freq0[ 7:0] <= dat_i[ 7:0];`
174			`if (sel_i[1]) freq0[15:8] <= dat_i[15:8];`
175			`end`
176			`7'd1:`
177			`begin`
178			`if (sel_i[0]) pw0[ 7:0] <= dat_i[ 7:0];`
179			`if (sel_i[1]) pw0[11:8] <= dat_i[11:8];`
180			`end`
181			`7'd2: begin`
182			`if (sel_i[0]) vt[0] <= dat_i[6:2];`
183			`if (sel_i[1]) begin`
184			`outctrl[0] <= dat_i[8];`
185			`filt[0] <= dat_i[9];`
186			`gate[0] <= dat_i[12];`
187			`sync[0] <= dat_i[13];`
188			`ringmod[0] <= dat_i[14];`
189			`test[0] <= dat_i[15];`
190			`end`
191			`end`
192			`7'd3: begin`
193			`if (sel_i[0]) attack0 <= dat_i[7:4];`
194			`if (sel_i[0]) decay0 <= dat_i[3:0];`
195			`if (sel_i[1]) relese0 <= dat_i[11:8];`
196			`if (sel_i[1]) sustain0 <= dat_i[15:12];`
197			`end`
198
199			`//---------------------------------------------------------`
200			`7'd4:`
201			`begin`
202			`if (sel_i[0]) freq1[ 7:0] <= dat_i[ 7:0];`
203			`if (sel_i[1]) freq1[15:8] <= dat_i[15:8];`
204			`end`
205			`7'd5:`
206			`begin`
207			`if (sel_i[0]) pw1[ 7:0] <= dat_i[ 7:0];`
208			`if (sel_i[1]) pw1[11:8] <= dat_i[11:8];`
209			`end`
210			`7'd6: begin`
211			`if (sel_i[0]) vt[1] <= dat_i[6:2];`
212			`if (sel_i[1]) begin`
213			`outctrl[1] <= dat_i[8];`
214			`filt[1] <= dat_i[9];`
215			`gate[1] <= dat_i[12];`
216			`sync[1] <= dat_i[13];`
217			`ringmod[1] <= dat_i[14];`
218			`test[1] <= dat_i[15];`
219			`end`
220			`end`
221			`7'd7: begin`
222			`if (sel_i[0]) attack1 <= dat_i[7:4];`
223			`if (sel_i[0]) decay1 <= dat_i[3:0];`
224			`if (sel_i[1]) relese1 <= dat_i[11:8];`
225			`if (sel_i[1]) sustain1 <= dat_i[15:12];`
226			`end`
227
228			`//---------------------------------------------------------`
229			`7'd8:`
230			`begin`
231			`if (sel_i[0]) freq2[ 7:0] <= dat_i[ 7:0];`
232			`if (sel_i[1]) freq2[15:8] <= dat_i[15:8];`
233			`end`
234			`7'd9:`
235			`begin`
236			`if (sel_i[0]) pw2[ 7:0] <= dat_i[ 7:0];`
237			`if (sel_i[1]) pw2[11:8] <= dat_i[11:8];`
238			`end`
239			`7'd10: begin`
240			`if (sel_i[0]) vt[2] <= dat_i[6:2];`
241			`if (sel_i[1]) begin`
242			`outctrl[2] <= dat_i[8];`
243			`filt[2] <= dat_i[9];`
244			`gate[2] <= dat_i[12];`
245			`sync[2] <= dat_i[5];`
246			`outctrl[0] <= dat_i[13];`
247			`ringmod[2] <= dat_i[14];`
248			`test[2] <= dat_i[15];`
249			`end`
250			`end`
251			`7'd11: begin`
252			`if (sel_i[0]) attack2 <= dat_i[7:4];`
253			`if (sel_i[0]) decay2 <= dat_i[3:0];`
254			`if (sel_i[1]) relese2 <= dat_i[11:8];`
255			`if (sel_i[1]) sustain2 <= dat_i[15:12];`
256			`end`
257
258			`//---------------------------------------------------------`
259			`7'd12:`
260			`begin`
261			`if (sel_i[0]) freq3[ 7:0] <= dat_i[ 7:0];`
262			`if (sel_i[1]) freq3[15:8] <= dat_i[15:8];`
263			`end`
264			`7'd13:`
265			`begin`
266			`if (sel_i[0]) pw3[ 7:0] <= dat_i[ 7:0];`
267			`if (sel_i[1]) pw3[11:8] <= dat_i[11:8];`
268			`end`
269			`7'd14: begin`
270			`if (sel_i[0]) vt[3] <= dat_i[6:2];`
271			`if (sel_i[1]) begin`
272			`outctrl[3] <= dat_i[8];`
273			`filt[3] <= dat_i[9];`
274			`gate[3] <= dat_i[12];`
275			`sync[3] <= dat_i[13];`
276			`ringmod[3] <= dat_i[14];`
277			`test[3] <= dat_i[15];`
278			`end`
279			`end`
280			`7'd15: begin`
281			`if (sel_i[0]) attack3 <= dat_i[7:4];`
282			`if (sel_i[0]) decay3 <= dat_i[3:0];`
283			`if (sel_i[1]) relese3 <= dat_i[11:8];`
284			`if (sel_i[1]) sustain3 <= dat_i[15:12];`
285			`end`
286
287			`//---------------------------------------------------------`
288			`7'd64: if (sel_i[0]) volume <= dat_i[3:0];`
289
290			`7'd68: begin`
291			`if (sel_i[1]) m_adr_o[15:14] <= dat_i[15:14];`
292			`end`
293			`7'd69:`
294			`begin`
295			`if (sel_i[0]) m_adr_o[23:16] <= dat_i[ 7:0];`
296			`if (sel_i[1]) m_adr_o[31:24] <= dat_i[15:8];`
297			`end`
298			`7'd70: begin`
299			`if (sel_i[0]) m_adr_o[39:32] <= dat_i[ 7:0];`
300			`if (sel_i[1]) m_adr_o[47:40] <= dat_i[15:8];`
301			`end`
302			`default: ;`
303			`endcase`
304			`end`
305			`end`
306			`end`
307
308
309			`always @(posedge clk_i)`
310			`if (cs) begin`
311			`case(adr_i[6:0])`
312			`7'd65: begin`
313			`vol_o <= 1'b1;`
314			`dat_o <= acc3[23:8];`
315			`end`
316			`7'd66: begin`
317			`vol_o <= 1'b1;`
318			`dat_o <= env3;`
319			`end`
320			`default: begin`
321			`dat_o <= env3;`
322			`vol_o <= 1'b0;`
323			`end`
324			`endcase`
325			`end`
326			`else begin`
327			`dat_o <= 16'b0;`
328			`vol_o <= 1'b0;`
329			`end`
330
331			`wire [11:0] alow;`
332
333			`// set wave table output address`
334			`always @(ibg or acc1 or acc0 or acc2 or acc3 or alow)`
335			`begin`
336			`m_adr_o[13:12] <= {ibg[2]\|ibg[3],ibg[1]\|ibg[3]};`
337			`m_adr_o[11:0] <= alow;`
338			`end`
339
340			`mux4to1 #(12) u11`
341			`(`
342			`.e(1'b1),`
343			`.s(m_adr_o[13:12]),`
344			`.i0({acc0[23:13],1'b0}),`
345			`.i1({acc1[23:13],1'b0}),`
346			`.i2({acc2[23:13],1'b0}),`
347			`.i3({acc3[23:13],1'b0}),`
348			`.z(alow)`
349			`);`
350
351			`// This counter controls channel multiplexing and the base`
352			`// operating frequency.`
353			`wire [7:0] cnt;`
354			`reg [7:0] cnt1,cnt2,cnt3;`
355			`counter #(8) u1`
356			`(`
357			`.rst(rst_i),`
358			`.clk(clk_i),`
359			`.ce(1'b1),`
360			`.ld(cnt==pClkDivide-1),`
361			`.d(8'd0),`
362			`.q(cnt)`
363			`);`
364
365			`// channel select signal`
366			`wire [1:0] sel = cnt[1:0];`
367
368
369			`// bus arbitrator for wave table access`
370			`wire [2:0] bgn;`
371			`PSGBusArb u2`
372			`(`
373			`.rst(rst_i),`
374			`.clk(clk_i),`
375			`.ce(1'b1),`
376			`.ack(1'b1),`
377			`.seln(bgn),`
378			`.req0(ibr[0]),`
379			`.req1(ibr[1]),`
380			`.req2(ibr[2]),`
381			`.req3(ibr[3]),`
382			`.req4(1'b0),`
383			`.req5(1'b0),`
384			`.req6(1'b0),`
385			`.req7(1'b0),`
386			`.sel0(ibg[0]),`
387			`.sel1(ibg[1]),`
388			`.sel2(ibg[2]),`
389			`.sel3(ibg[3]),`
390			`.sel4(),`
391			`.sel5(),`
392			`.sel6(),`
393			`.sel7()`
394			`);`
395
396			`// note generator - multi-channel`
397			`PSGNoteGen u3`
398			`(`
399			`.rst(rst_i),`
400			`.clk(clk_i),`
401			`.cnt(cnt),`
402			`.br(ibr),`
403			`.bg(ibg),`
404			`.ack(m_ack_i),`
405			`.bgn(bgn),`
406			`.test(test),`
407			`.vt0(vt[0]),`
408			`.vt1(vt[1]),`
409			`.vt2(vt[2]),`
410			`.vt3(vt[3]),`
411			`.freq0(freq0),`
412			`.freq1(freq1),`
413			`.freq2(freq2),`
414			`.freq3(freq3),`
415			`.pw0(pw0),`
416			`.pw1(pw1),`
417			`.pw2(pw2),`
418			`.pw3(pw3),`
419			`.acc0(acc0),`
420			`.acc1(acc1),`
421			`.acc2(acc2),`
422			`.acc3(acc3),`
423			`.wave(m_dat_i),`
424			`.sync(sync),`
425			`.ringmod(ringmod),`
426			`.o(ngo)`
427			`);`
428
429			`// envelope generator - multi-channel`
430			`PSGEnvGen u4`
431			`(`
432			`.rst(rst_i),`
433			`.clk(clk_i),`
434			`.cnt(cnt),`
435			`.gate(gate),`
436			`.attack0(attack0),`
437			`.attack1(attack1),`
438			`.attack2(attack2),`
439			`.attack3(attack3),`
440			`.decay0(decay0),`
441			`.decay1(decay1),`
442			`.decay2(decay2),`
443			`.decay3(decay3),`
444			`.sustain0(sustain0),`
445			`.sustain1(sustain1),`
446			`.sustain2(sustain2),`
447			`.sustain3(sustain3),`
448			`.relese0(relese0),`
449			`.relese1(relese1),`
450			`.relese2(relese2),`
451			`.relese3(relese3),`
452			`.o(env)`
453			`);`
454
455			`// shape output according to envelope`
456			`PSGShaper u5`
457			`(`
458			`.clk_i(clk_i),`
459			`.ce(1'b1),`
460			`.tgi(ngo),`
461			`.env(env),`
462			`.o(out2)`
463			`);`
464
465			`always @(posedge clk_i)`
466			`cnt1 <= cnt;`
467			`always @(posedge clk_i)`
468			`cnt2 <= cnt1;`
469			`always @(posedge clk_i)`
470			`cnt3 <= cnt2;`
471
472			`// Sum the channels not going to the filter`
473			`PSGChannelSummer u6`
474			`(`
475			`.clk_i(clk_i),`
476			`.cnt(cnt1),`
477			`.outctrl(outctrl),`
478			`.tmc_i(out2),`
479			`.o(out1)`
480			`);`
481
482			`always @(posedge clk_i)`
483			`out1a <= out1;`
484
485			`// Sum the channels going to the filter`
486			`PSGChannelSummer u7`
487			`(`
488			`.clk_i(clk_i),`
489			`.cnt(cnt1),`
490			`.outctrl(filt),`
491			`.tmc_i(out2),`
492			`.o(filtin1)`
493			`);`
494
495			`// The FIR filter`
496			`PSGFilter u8`
497			`(`
498			`.rst(rst_i),`
499			`.clk(clk_i),`
500			`.cnt(cnt2),`
501			`.wr(we_i && stb_i && adr_i[6:4]==3'b101),`
502			`.adr(adr_i[3:0]),`
503			`.din({dat_i[15],dat_i[11:0]}),`
504			`.i(filtin1[21:7]),`
505			`.o(filt_o)`
506			`);`
507
508			`// Sum the filtered and unfiltered output`
509			`PSGOutputSummer u9`
510			`(`
511			`.clk_i(clk_i),`
512			`.cnt(cnt3),`
513			`.ufi(out1a),`
514			`.fi({filt_o,7'b0}),`
515			`.o(out3)`
516			`);`
517
518			`// Last stage:`
519			`// Adjust output according to master volume`
520			`PSGMasterVolumeControl u10`
521			`(`
522			`.rst_i(rst_i),`
523			`.clk_i(clk_i),`
524			`.i(out3[21:6]),`
525			`.volume(volume),`
526			`.o(out4)`
527			`);`
528
529			`assign o = out4[19:2];`
530
531			`endmodule`
532