From c3bcc38aaf21ce2036ea66b9e5f764e6d3e7ac7f Mon Sep 17 00:00:00 2001
From: Michael Gernoth <michael@gernoth.net>
Date: Thu, 15 May 2008 22:29:51 +0200
Subject: [PATCH] cleanup clocks

---
 galaxian/src/dcm.v         |  2 +-
 galaxian/src/mc_adec.v     |  4 +--
 galaxian/src/mc_bram_if.v  |  4 +--
 galaxian/src/mc_clock.v    | 54 ++++++++++++++++++++++++--------------
 galaxian/src/mc_hv_count.v |  9 +++----
 galaxian/src/mc_ld_pls.v   |  4 +--
 galaxian/src/mc_top.v      | 20 +++++++-------
 galaxian/src/mc_video.v    |  8 +++---
 8 files changed, 59 insertions(+), 46 deletions(-)

diff --git a/galaxian/src/dcm.v b/galaxian/src/dcm.v
index 64541bc..9f51aed 100644
--- a/galaxian/src/dcm.v
+++ b/galaxian/src/dcm.v
@@ -55,7 +55,7 @@ module mc_dcm(CLKIN_IN,
                        .STATUS());
    defparam DCM_SP_INST.CLK_FEEDBACK = "1X";
    defparam DCM_SP_INST.CLKDV_DIVIDE = 2.0;
-   defparam DCM_SP_INST.CLKFX_DIVIDE = 27;
+   defparam DCM_SP_INST.CLKFX_DIVIDE = 13;
    defparam DCM_SP_INST.CLKFX_MULTIPLY = 4;
    defparam DCM_SP_INST.CLKIN_DIVIDE_BY_2 = "FALSE";
    defparam DCM_SP_INST.CLKIN_PERIOD = 8.000;
diff --git a/galaxian/src/mc_adec.v b/galaxian/src/mc_adec.v
index 65525ba..2fa91fd 100644
--- a/galaxian/src/mc_adec.v
+++ b/galaxian/src/mc_adec.v
@@ -137,8 +137,8 @@ wire   W_NMI_ONn = W_9N_Q[1]; //  galaxian
 reg    W_6S1_Q,W_6S1_Qn;
 reg    W_6S2_Qn;
 
-//assign O_WAITn = W_6S1_Qn;
-assign O_WAITn = 1'b1 ; // No Wait
+assign O_WAITn = W_6S1_Qn;
+//assign O_WAITn = 1'b1 ; // No Wait
 
 always@(posedge I_CPU_CLK or negedge I_V_BLn)
 begin
diff --git a/galaxian/src/mc_bram_if.v b/galaxian/src/mc_bram_if.v
index 8476f25..1374c92 100644
--- a/galaxian/src/mc_bram_if.v
+++ b/galaxian/src/mc_bram_if.v
@@ -266,7 +266,7 @@ alt_ram_256_5 LRAM(
 .outclock(~I_CLK),
 .address(I_ADDR),
 .data(I_D),
-.wren(I_WE),
+.wren(~I_WE),
 .q(W_D)
 
 );
@@ -282,7 +282,7 @@ RAMB4_S8 LRAM(
 .DI({3'b000,I_D}),
 .DO(W_D),
 .EN(1'b1),
-.WE(I_WE),
+.WE(~I_WE),
 .RST(1'b0)
 
 );
diff --git a/galaxian/src/mc_clock.v b/galaxian/src/mc_clock.v
index 43cadb4..a88d95c 100644
--- a/galaxian/src/mc_clock.v
+++ b/galaxian/src/mc_clock.v
@@ -17,47 +17,61 @@
 
 module mc_clock(
 
-I_CLK_18M,
+I_CLK_36M,
+O_CLK_18M,
 O_CLK_12M,
-O_CLK_06M,
-O_CLK_06Mn
+O_CLK_06M
 
 );
 
-input  I_CLK_18M;
+input I_CLK_36M;
+output O_CLK_18M;
 output O_CLK_12M;
 output O_CLK_06M;
-output O_CLK_06Mn;
 
 // 2/3 clock divider(duty 33%)
-reg [1:0] clk_ff1,clk_ff2;
 //I_CLK   1010101010101010101
 //c_ff10  0011110011110011110
 //c_ff11  0011000011000011000
 //c_ff20  0000110000110000110
 //c_ff21  0110000110000110000
 //O_12M   0000110110110110110
-always @(posedge I_CLK_18M)
+reg [1:0] state;
+reg clk_12m;
+initial state = 0;
+initial clk_12m = 0;
+
+// 2/3 clock         (duty 66%)
+always @(negedge I_CLK_36M)
 begin
-   clk_ff1[0] <= ~clk_ff1[0] | clk_ff1[1];
-   clk_ff1[1] <= ~clk_ff1[0] & ~clk_ff1[1];
-   clk_ff2[0] <= clk_ff1[0] & clk_ff1[1];
+   case (state)
+      2'd0: state <= 2'd1;
+      2'd1: state <= 2'd2;
+      2'd2: state <= 2'd0;
+      2'd3: state <= 2'd0;
+   endcase
+
+   if (state == 2'd2)
+      clk_12m = 1;
+   else
+      clk_12m = 0;
 end
-always @(negedge I_CLK_18M)
-   clk_ff2[1] <= ~clk_ff1[0] & ~clk_ff1[1];
 
-// 2/3 clock         (duty 66%)
-assign O_CLK_12M = clk_ff2[0]| clk_ff2[1];
- 
+assign O_CLK_12M = clk_12m;
+
+reg CLK_18M;
+always @(posedge I_CLK_36M)
+begin
+   CLK_18M <= ~ CLK_18M;
+end
+assign O_CLK_18M = CLK_18M;
+
 // 1/3 clock divider (duty 50%)
-reg CLK_6M , CLK_6Mn;
+reg CLK_6M;
 always @(posedge O_CLK_12M)
 begin
-   CLK_6Mn <=  CLK_6M;
    CLK_6M  <= ~CLK_6M;
 end
 assign O_CLK_06M = CLK_6M;
-assign O_CLK_06Mn = CLK_6Mn;
-
 
-endmodule
\ No newline at end of file
+endmodule
diff --git a/galaxian/src/mc_hv_count.v b/galaxian/src/mc_hv_count.v
index aa34b40..06f3023 100644
--- a/galaxian/src/mc_hv_count.v
+++ b/galaxian/src/mc_hv_count.v
@@ -61,12 +61,11 @@ assign O_H_CNT  = H_CNT[8:0];
 
 //-------   H_SYNC     ----------------------------------------
 
-reg    H_SYNCn;
-wire   H_SYNC = ~H_SYNCn;
+reg	H_SYNC;
 always@(posedge H_CNT[4] or negedge H_CNT[8]) 
 begin
-   if(H_CNT[8]==1'b0) H_SYNCn <= 1'b1;
-   else   H_SYNCn <= ~(~H_CNT[6]& H_CNT[5]);
+   if(H_CNT[8]==1'b0) H_SYNC <= 1'b0;
+   else   H_SYNC <= (~H_CNT[6]& H_CNT[5]);
 end
 
 assign O_H_SYNC = H_SYNC;
@@ -124,4 +123,4 @@ assign O_V_BL2n = V_BL2n;
 
 assign O_C_BLn = ~(~V_BLn | H_CNT[8]);
 
-endmodule
\ No newline at end of file
+endmodule
diff --git a/galaxian/src/mc_ld_pls.v b/galaxian/src/mc_ld_pls.v
index 51a2934..01fc558 100644
--- a/galaxian/src/mc_ld_pls.v
+++ b/galaxian/src/mc_ld_pls.v
@@ -46,7 +46,7 @@ output O_MLDn;
 output O_SLDn;
 
 reg    W_5C_Q;
-always@(posedge I_CLK_6M)
+always@(negedge I_CLK_6M)
    W_5C_Q <= I_H_CNT[0];
 
 //    Parts 4D
@@ -83,7 +83,7 @@ logic_74xx139 U_4C1(
 );
 
 reg    W_4C1_Q3;
-always@(negedge I_CLK_6M)    // 2004-9-22 added
+always@(posedge  I_CLK_6M)    // 2004-9-22 added
    W_4C1_Q3 <= W_4C1_Q[3];
 
 reg    W_4C2_B;
diff --git a/galaxian/src/mc_top.v b/galaxian/src/mc_top.v
index 99a4a6a..4cabd74 100644
--- a/galaxian/src/mc_top.v
+++ b/galaxian/src/mc_top.v
@@ -89,7 +89,8 @@ output O_VGA_V_SYNCn;
 
 wire   W_RESETn = |(~I_PSW[8:5]);
 //------ CLOCK GEN ---------------------------
-wire   I_CLK_18432M;
+wire   W_CLK_18M;
+wire   W_CLK_36M;
 wire   W_CLK_12M,WB_CLK_12M;
 wire   W_CLK_6M,WB_CLK_6M;
 wire   W_STARS_CLK;
@@ -97,7 +98,7 @@ wire   W_STARS_CLK;
 mc_dcm clockgen(
 .CLKIN_IN(I_CLK_125M),
 .RST_IN(! W_RESETn),
-.CLKFX_OUT(I_CLK_18432M)
+.CLKFX_OUT(W_CLK_36M)
 );
 
 //------ H&V COUNTER -------------------------
@@ -144,7 +145,8 @@ wire   [7:0]W_VID_DO;
 
 mc_clock MC_CLK(
 
-.I_CLK_18M(I_CLK_18432M),
+.I_CLK_36M(W_CLK_36M),
+.O_CLK_18M(W_CLK_18M),
 .O_CLK_12M(WB_CLK_12M),
 .O_CLK_06M(WB_CLK_6M)
 
@@ -329,7 +331,7 @@ wire	VIB_SW = died & (&on_game[1:0]);
 
 fpga_arcade_if pspad(
 
-.CLK_18M432(I_CLK_18432M),
+.CLK_18M432(W_CLK_18M),
 .I_RSTn(W_RESETn),
 .psCLK(psCLK),
 .psSEL(psSEL),
@@ -444,7 +446,7 @@ wire   [1:0]W_VID;
 wire   [2:0]W_COL;
 
 mc_video MC_VID(
-.I_CLK_18M(I_CLK_18432M),
+.I_CLK_18M(W_CLK_18M),
 .I_CLK_12M(W_CLK_12M),
 .I_CLK_6M(W_CLK_6M),
 .I_H_CNT(W_H_CNT),
@@ -503,7 +505,7 @@ wire   [1:0]W_STARS_B;
 
 mc_stars MC_STARS( 
 
-.I_CLK_18M(I_CLK_18432M),
+.I_CLK_18M(W_CLK_18M),
 `ifdef DEVICE_CYCLONE
 .I_CLK_6M(~WB_CLK_6M),
 `endif
@@ -615,7 +617,7 @@ wire   [7:0]W_SDAT_B;
 
 mc_sound_b MC_SOUND_B(
 
-.I_CLK1(I_CLK_18432M),
+.I_CLK1(W_CLK_18M),
 .I_CLK2(W_CLK_6M),
 .I_RSTn(rst_count[3]),
 .I_SW({&on_game[1:0],W_HIT,W_FIRE}),
@@ -639,7 +641,7 @@ assign  O_SOUND_OUT_R = W_DAC_B;
 
 dac wav_dac_a(
 
-.Clk(I_CLK_18432M), 
+.Clk(W_CLK_18M), 
 .Reset(~W_RESETn),
 .DACin(W_SDAT_A),
 .DACout(W_DAC_A)
@@ -648,7 +650,7 @@ dac wav_dac_a(
 
 dac wav_dac_b(
 
-.Clk(I_CLK_18432M), 
+.Clk(W_CLK_18M), 
 .Reset(~W_RESETn),
 .DACin(W_SDAT_B),
 .DACout(W_DAC_B)
diff --git a/galaxian/src/mc_video.v b/galaxian/src/mc_video.v
index c184923..a12155d 100644
--- a/galaxian/src/mc_video.v
+++ b/galaxian/src/mc_video.v
@@ -119,7 +119,7 @@ end
 
 mc_ld_pls LD_PLS(
 
-.I_CLK_6M(~I_CLK_6M),
+.I_CLK_6M(I_CLK_6M),
 .I_H_CNT(I_H_CNT),
 .I_3D_DI(W_3D),
 
@@ -339,16 +339,14 @@ begin
 end
 
 wire   [7:0]W_LRAM_A = W_45T_Q^{8{W_H_FLIP1X}};
-wire   W_LRAM_WE = ~I_CLK_6M;
 
 wire   [4:0]W_LRAM_DI;
 wire   [4:0]W_LRAM_DO;
 
 reg    [1:0]W_RV;
 reg    [2:0]W_RC;
-wire   W_1U_CLK = ~I_CLK_6M;
 
-always@(posedge W_1U_CLK)
+always@(negedge I_CLK_6M)
 begin
       W_RV <= W_LRAM_DO[1:0];    
       W_RC <= W_LRAM_DO[4:2];
@@ -379,7 +377,7 @@ mc_lram LRAM(
 
 .I_CLK(I_CLK_18M),
 .I_ADDR(W_LRAM_A),
-.I_WE(W_LRAM_WE),
+.I_WE(I_CLK_6M),
 .I_D(W_LRAM_DI),
 .O_Dn(W_LRAM_DO)
 
-- 
2.39.5