Working version with loader from schmidt trigger

spectrum.sv

@@ -18,7 +18,8 @@ module spectrum(output wire[7:0] LED,
 					 output wire VGA_VS,
                 input wire[3:0] SW,         // 0 = ROM selection, 1 = enable/disable interrupts, 2 = turbo speed
                 output wire[33:0] GPIO_1,    // Exports CPU chip pins,
-					 output wire buzzer_out
+					 output wire buzzer_out,
+					 input wire raw_loader_in
 );
 `default_nettype none
 
@@ -93,7 +94,10 @@ assign io_we = nIORQ==0 && nRD==1 && nWR==0;
 always @(*) // always_comb
 begin
     case ({nIORQ,nRD,nWR})
-        // -------------------------------- Memory read --------------------------------
+        // -------------------------------- 
+		  
+		  
+		  // Memory read --------------------------------
         3'b101: begin
                 casez (A[15:14])
                     2'b00:  D[7:0] = rom_data;
@@ -139,13 +143,13 @@ wire[7:0] ram0_data;
 // "A" port is the CPU side, "B" port is the VGA image generator in the ULA
 ram16 ram0(
     .clock(CLOCK_50),
-
+//    .clock_a(clk_cpu),
     .address_a(A[13:0]),
     .data_a(D),
     .q_a(ram0_data),
     .wren_a(RamWE),
-//    .wren_a(0),
 
+//    .clock_b(clk_vram),
     .address_b({1'b0, vram_address}),
     .data_b(8'b0),
     .q_b(vram_data),
@@ -157,7 +161,7 @@ ram16 ram0(
 //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 wire[7:0] ram1_data;
 ram32 ram1(
-    .clock(clk_cpu),
+    .clock(clk_vram),
 
     .address(A[14:0]),
     .data(D),
@@ -170,6 +174,7 @@ ram32 ram1(
 //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 wire clk_cpu;                   // Global CPU clock of 3.5 MHz
 assign LED[2:2] = SW[2:2];      // Glow red when in turbo mode (7.0 MHz)
+assign LED[3:3] = raw_loader_in; // feedback from audio in
 wire [12:0] vram_address;       // ULA video block requests a byte from the video RAM
 wire [7:0] vram_data;           // ULA video block reads a byte from the video RAM
 wire vs_nintr;                  // Generates a vertical retrace interrupt
@@ -213,6 +218,7 @@ ula ula_(
     .AUD_ADCDAT (AUD_ADCDAT),
     .beeper (beeper),
 	 .beep(buzzer_out),
+	 .raw_loader_in(raw_loader_in),
 
     //-------- VGA connector --------------------
     .VGA_R (VGA_R),