First working simulation of 'hello, world' :)

verilog/controller/controller.v

@@ -16,6 +16,7 @@ module CONTROLLER (
         amp_out,    // amplitude output
         coeff_out,  // 8-bit coefficient data out
         coeff_stb,  // '1' when coeff_out holds new coefficient data
+        clear_states, // outputs '1' to reset filter states
         period_done_in // should be '1' when the source finished a period
     );
 
@@ -26,6 +27,7 @@ module CONTROLLER (
     input rst_an;
 
 	//////////// OUTPUTS //////////
+    output reg clear_states;
     output reg ldq;
     output reg coeff_stb;
     output reg signed [9:0] coeff_out;
@@ -165,13 +167,14 @@ module CONTROLLER (
             if (serve_pitch_data)
             begin
                 duration   <= dur_tmp;
-                amp_out    <= {4'b0000, amp_tmp[15:4]};
+                //amp_out    <= {4'b0000, amp_tmp[15:4]};
+                amp_out    <= {amp_tmp[13:0],2'b00};
                 period_out <= period_tmp;
             end
 
             if (set_ldq == 1)
                 ldq <= 1;
-            else if (reset_ldq == 1)
+            else if (data_stb == 1)
                 ldq <= 0;
 
             if ((period_done_in == 1) && (!serve_next_allo_data))
@@ -243,25 +246,29 @@ module CONTROLLER (
         dur_load    <= 0;
         allo_load   <= 0;
         load_cur_cmd <= 0;
-        set_ldq     <= 0;
+        set_ldq      <= 0;
-        reset_ldq   <= 0;
+        clear_states <= 0;
+
         serve_pitch_data <= 0;
         dur_cnt_clear <= 0;
 
         case (cur_state)
             S_IDLE:
                 begin
-                    set_ldq <= 1;
                     if (serve_next_allo_data == 1)
                     begin
-                        // we've run out of allophone data .. 
+                        // we've run out of allophone data ..
                     end
                     if (data_stb == 1)
                     begin
                         allo_load  <= 1;
+                        //reset_ldq  <= 1;
                         next_state <= S_JMPADDR1;
-                    end                    
+                    end
-                    rom_addr_sel <= ROM_ADDR_ZERO;                    
+                    else
+                        set_ldq <= 1;
+
+                    rom_addr_sel <= ROM_ADDR_ZERO;         
                 end
             S_JMPADDR1:
                 begin
@@ -285,7 +292,6 @@ module CONTROLLER (
                     // perform jmp                    
                     rom_addr_sel <= ROM_ADDR_JMP;
                     next_state <= S_CMDDECODE;
-                    reset_ldq <= 1;
                 end
             S_CMDDECODE:
                 begin
@@ -334,7 +340,16 @@ module CONTROLLER (
                     begin
                         serve_pitch_data <= 1;
                         dur_cnt_clear    <= 1;
-                        next_state <= (cur_cmd == 4'd2) ? S_LOADCOEF1 : S_CMDDECODE;
+                        if (cur_cmd == 4'd2)
+                        begin
+                            clear_states <= 1;
+                            next_state <= S_LOADCOEF1;
+                        end
+                        else
+                        begin
+                            next_state <= S_CMDDECODE;
+                        end
+                        
                     end
                 end                            
             S_LOADCOEF1:

verilog/controller/controller_tb.v

@@ -11,6 +11,7 @@ module CONTROLLER_TB;
     reg [5:0] data_in;
     reg data_stb, serve_next;
     reg period_done;
+    wire clear_states;
     
     wire ldq;
     wire [9:0] coeff;
@@ -29,6 +30,7 @@ module CONTROLLER_TB;
         .amp_out    (amp),
         .coeff_out  (coeff),
         .coeff_stb  (coeff_load),
+        .clear_states (clear_states),
         .period_done_in (period_done)
     );
 

verilog/controller/xlat.v

@@ -24,7 +24,7 @@ module XLAT (
     output reg [9:0] c10_out;
     wire sign;
 
-    assign sign = c8_in[7];
+    assign sign = ~c8_in[7];
 
     always@(*)
     begin

verilog/filter/filter.v

@@ -20,7 +20,7 @@ module FILTER (
         // coefficient loading interface
         coef_in,        // 10 bit sign-magnitude coefficient
         coef_load,      // pulse '1' to load the coefficient into the internal register
-
+        clear_states,   // set to '1' to reset internal filter states
         // signal I/O and handshaking
         sig_in,         // 16-bit (scaled) source input signal
         sig_out,        // 16-bit filter output signal
@@ -39,6 +39,7 @@ module FILTER (
     input signed [15:0] sig_in;
     input signed [9:0]  coef_in;
     input start, coef_load;
+    input clear_states; // zero all states
 
 	//////////// FILTER OUTPUTS //////////
 	output wire signed [15:0] sig_out;
@@ -56,7 +57,7 @@ module FILTER (
     reg do_accu;                        // if 1, the accumulator is updated
     reg double_mode;                    // if 1, the input to the accumulator is x2
     reg update_states;                  // shift the state registers
-    reg clear_states;                   // zero all states
+    
     reg update_coeffs;                  // shift the coefficient registers
     reg [3:0] cur_state;                // current FSM state
     reg [3:0] next_state;               // next FSM state

verilog/filter/filter_tb.v

@@ -6,7 +6,7 @@
 //
 
 module FILTER_TB;
-    reg clk, rst_an, start, coef_load, check_finish; 
+    reg clk, rst_an, start, coef_load, check_finish, clear_states; 
     reg signed [15:0] sig_in;
     reg signed [9:0]  coef_in;
     reg        [3:0]  reg_sel;
@@ -22,6 +22,7 @@ module FILTER_TB;
         .rst_an     (rst_an),
         .coef_in    (coef_in),
         .coef_load  (coef_load),
+        .clear_states (clear_states),
         .sig_in     (sig_in),
         .sig_out    (sig_out),
         .start      (start),
@@ -41,6 +42,7 @@ module FILTER_TB;
         coef_in     = 0;
         coef_load   = 0;
         start       = 0;
+        clear_states  = 0;
         check_finish  = 0;
 
         #10
@@ -52,29 +54,29 @@ module FILTER_TB;
         #10
         coef_load = 1;
         // section 1
-        coef_in     = 10'h3C9;
+        coef_in     = 10'h1C9;
         #10
-        coef_in     = 10'h1E4;
+        coef_in     = 10'h3E4;
         #10
         // section 2
-        coef_in     = 10'h2B8;
+        coef_in     = 10'h0B8;
         #10
-        coef_in     = 10'h1CF;
+        coef_in     = 10'h3CF;
         #10
         // section 3
-        coef_in     = 10'h238;
+        coef_in     = 10'h038;
         #10
-        coef_in     = 10'h080;
+        coef_in     = 10'h280;
         #10
         // section 4
-        coef_in     = 10'h195;
+        coef_in     = 10'h395;
         #10
-        coef_in     = 10'h1BF;
+        coef_in     = 10'h3BF;
         #10
         // section 5
-        coef_in     = 10'h135;
+        coef_in     = 10'h335;
         #10
-        coef_in     = 10'h1BF;
+        coef_in     = 10'h3BF;
         #10
         // section 6
         coef_in     = 10'h000;
@@ -118,7 +120,7 @@ module FILTER_TB;
         #10    
         coef_load = 0;
         start = 1;
-        #10000;
+        #20000;
         check_finish = 1;
     end
 

verilog/speech256_top/speech256_top.v

@@ -7,12 +7,14 @@
 // 
 
 module SPEECH256_TOP (
-        clk,        // global Speech256 clock
+        clk,        // global Speech256 clock (256*10kHz)
         rst_an,     
         ldq,        // load request, is high when new allophone can be loaded
         data_in,    // allophone input
         data_stb,   // allophone strobe input
-        dac_out,    // 1-bit PWM DAC output
+        pwm_out,    // 1-bit PWM DAC output
+        sample_out,
+        sample_stb
     );
 
 	//////////// CLOCK //////////
@@ -22,8 +24,10 @@ module SPEECH256_TOP (
     input rst_an;
 
 	//////////// OUTPUTS //////////
-	output dac_out;
+	output pwm_out;
     output ldq;
+    output signed [15:0] sample_out;
+    output sample_stb;
 
 	//////////// INPUTS //////////
     input [5:0] data_in;
@@ -35,6 +39,7 @@ module SPEECH256_TOP (
     wire signed [15:0] sig_source;
     wire signed [15:0] sig_filter;
     wire period_done;
+    wire clear_states;
 
     wire [7:0]  period;
     wire [7:0]  dur;
@@ -60,6 +65,7 @@ module SPEECH256_TOP (
         .rst_an     (rst_an),
         .coef_in    (coef_bus),
         .coef_load  (coef_load),
+        .clear_states (clear_states),
         .sig_in     (sig_source),
         .sig_out    (sig_filter),
         .start      (pwmdac_ack),
@@ -71,7 +77,7 @@ module SPEECH256_TOP (
         .rst_an     (rst_an),
         .din        (sig_filter[15:8]),
         .din_ack    (pwmdac_ack),
-        .dacout     (dac_out)
+        .dacout     (pwm_out)
     );
 
     CONTROLLER u_controller (
@@ -84,9 +90,13 @@ module SPEECH256_TOP (
         .amp_out    (amp),
         .coeff_out  (coef_bus),
         .coeff_stb  (coef_load),
+        .clear_states (clear_states),
         .period_done_in (period_done)
     );
 
+    assign sample_out = sig_filter[15:0];
+    assign sample_stb = src_strobe;
+
     always @(posedge clk, negedge rst_an)
     begin
         if (rst_an == 0)

verilog/speech256_top/speech256_top_tb.v

@@ -9,7 +9,12 @@ module SPEECH256_TOP_TB;
     reg clk, rst_an; 
     reg [5:0] data_in;
     reg data_stb;
-    wire ldq,dac_out;
+    wire sample_stb;
+    wire signed [15:0] sample_out;
+    wire ldq,pwm_out;
+
+    reg [7:0] allophones[0:10];
+    reg [3:0] allo_idx;
 
     SPEECH256_TOP u_speech256_top (
         .clk        (clk),
@@ -17,34 +22,65 @@ module SPEECH256_TOP_TB;
         .ldq        (ldq),
         .data_in    (data_in),
         .data_stb   (data_stb),
-        .dac_out    (dac_out)
+        .pwm_out    (pwm_out),
+        .sample_out (sample_out),
+        .sample_stb (sample_stb)
     );
 
     integer fd; // file descriptor
 
     initial
     begin
+        // hello, world
+        allophones[0] = 6'h1B;
+        allophones[1] = 6'h07;
+        allophones[2] = 6'h2D;
+        allophones[3] = 6'h35;
+        allophones[4] = 6'h03;
+        allophones[5] = 6'h2E;
+        allophones[6] = 6'h1E;
+        allophones[7] = 6'h33;
+        allophones[8] = 6'h2D;
+        allophones[9] = 6'h15;
+        allophones[10] = 6'h03;
+        allophones[11] = 6'h00;
+
         fd = $fopen("dacout.sw","wb");
         $dumpfile ("speech256_top.vcd");
         $dumpvars;
         clk = 0;
         rst_an = 0;
-        data_stb = 0;
+        allo_idx = 0;
         #5
-        rst_an = 1;
+        rst_an <= 1;
-        #5
+        //#5
-        data_in = 7;
+        //#9000000
-        data_stb = 1;
-        #5
-        data_stb = 0;
-        #300000
         //$fclose(fd);
-        $finish;
+        //$finish;
     end
 
+    reg last_sample_stb;
     always @(posedge clk)
-    begin   
+    begin
-        $fwrite(fd,"%u", {31'd0,dac_out});
+        // check for new output sample
+        if ((sample_stb == 1) && (last_sample_stb != sample_stb))
+        begin
+            $fwrite(fd,"%u", $signed( {sample_out, 16'h0000} ));
+        end
+        last_sample_stb <= sample_stb;
+
+        // check for next allophone
+        if ((ldq == 1) && (data_stb == 0))
+        begin
+            data_stb <= 1;
+            data_in  <= allophones[allo_idx];
+            $display("Allophone %d", allo_idx);
+            allo_idx <= allo_idx + 1;
+            if (allo_idx == 11)
+                $finish;
+        end
+        else
+            data_stb <= 0;
     end
 
     always