speed up the presentation of registered wb data to the gpmc

2 files changed, 20 insertions, 13 deletions

diff --git a/usrp2/gpmc/gpmc.v b/usrp2/gpmc/gpmc.v
index 1963af6e6..56f879abc 100644
--- a/usrp2/gpmc/gpmc.v
+++ b/usrp2/gpmc/gpmc.v
@@ -12,7 +12,7 @@ module gpmc
 
    wire 	EM_output_enable = (~EM_NOE & (~EM_NCS4 | ~EM_NCS6));
    wire [15:0] 	EM_D_ram;
-   reg [15:0] 	EM_D_wb;
+   wire [15:0] 	EM_D_wb;
 
    assign EM_D = ~EM_output_enable ? 16'bz : ~EM_NCS4 ? EM_D_ram : EM_D_wb;
 
@@ -44,10 +44,13 @@ module gpmc
 	  wb_sel_o <= ~EM_NBE;
        end
 
+   reg [15:0] EM_D_wb_reg;
    always @(posedge wb_clk)
      if(wb_ack_i)
-       EM_D_wb <= wb_dat_miso;
+       EM_D_wb_reg <= wb_dat_miso;
 
+   assign EM_D_wb = wb_ack_i ? wb_dat_miso : EM_D_wb_reg;
+   
    // stb, oe_del, we_del
    assign wb_cyc_o = wb_stb_o;
 
diff --git a/usrp2/models/gpmc_model.v b/usrp2/models/gpmc_model.v
index ce3acaacf..38dde1fa5 100644
--- a/usrp2/models/gpmc_model.v
+++ b/usrp2/models/gpmc_model.v
@@ -25,16 +25,18 @@ module gpmc_model
       input [10:0] addr;
       input [15:0] data;
       begin
-	 #2;
+	 #2.3;
 	 EM_A <= addr[10:1];
 	 EM_D_int <= data;
-	 #4;
+	 #2.01;
 	 EM_NCS6 <= 0;
-	 #5;
+	 #14;
 	 EM_NWE <= 0;
-	 #41;
-	 EM_NWE <= 1;
+	 #77.5;
 	 EM_NCS6 <= 1;
+	 //#1.5;
+	 EM_NWE <= 1;
+	 #6;
 	 EM_A <= 10'bz;
 	 EM_D_int <= 16'bz;
       end
@@ -43,17 +45,19 @@ module gpmc_model
    task GPMC_Read;
       input [10:0] addr;
       begin
-	 #2;
+	 #1.3;
 	 EM_A <= addr[10:1];
-	 #4;
+	 #3;
 	 EM_NCS6 <= 0;
-	 #5;
+	 #14;
 	 EM_NOE <= 0;
-	 #41;
-	 EM_NOE <= 1;
+	 #77.5;
 	 EM_NCS6 <= 1;
-	 EM_A <= 10'bz;
+	 //#1.5;
 	 $display("Data Read from GPMC: %X",EM_D);
+	 EM_NOE <= 1;
+	 #254;
+	 EM_A <= 10'bz;
       end
    endtask // GPMC_Read