Initial commit.

1 files changed, 35 insertions, 0 deletions

diff --git a/sim/memory.sv b/sim/memory.sv
new file mode 100644
index 0000000..0eb1233
--- /dev/null
+++ b/sim/memory.sv
@@ -0,0 +1,35 @@
+module memory
+    #(  parameter   UROM        = "<no file specified>"
+    ,   parameter   UIP_BITS    = 15
+    ,   parameter   UROM_BITS   = 8
+    ,   parameter   BUS_BITS    = 16
+    ,   parameter   IMAGE       = "<no file specified>"
+    ,   parameter   BYTE_BITS   = 8
+    )
+    (   input   bit                 clk
+    ,   input   bit                 reset
+    ,   input   bit [UIP_BITS-1:0]  uip
+    ,   inout   bit [BUS_BITS-1:0]  abus
+    ,   inout   bit [BUS_BITS-1:0]  dbus
+    );
+
+bit [BYTE_BITS-1:0] storage [0:(1<<BUS_BITS)-1];
+initial $readmemh(IMAGE, storage);
+
+typedef enum
+    { STORE
+    , OUTDATA
+    } CtrlBit;
+
+bit [UROM_BITS-1:0] ctrl;
+urom#(UROM, UIP_BITS, UROM_BITS) urom(uip, ctrl);
+
+assign dbus = ctrl[OUTDATA] ? {{(BUS_BITS-BYTE_BITS){1'b0}}, storage[abus]} : {(BUS_BITS){1'bZ}};
+
+always @(posedge clk) begin
+    if (ctrl[STORE]) begin
+        storage[abus] <= dbus[BYTE_BITS-1:0];
+    end
+end
+
+endmodule