add concept of 'board' for seperate ucfs and top level modules

1 files changed, 31 insertions, 0 deletions

diff --git a/hdl/main_sp605.v b/hdl/main_sp605.v
new file mode 100644
index 0000000..1b4f9f2
--- /dev/null
+++ b/hdl/main_sp605.v
@@ -0,0 +1,31 @@
+// very minimal example top-level module
+
+module main (
+    output reg [3:0] gpio_led,
+    input wire [3:0] gpio_switch,
+    input wire SYSTEMCLOCK,
+    input wire PUSH_BUTTON_RESET_RAW // this is active low
+    );
+
+    wire reset;
+    assign reset = !PUSH_BUTTON_RESET_RAW;
+
+    reg [25:0] throb_counter = 0;
+
+    always @(posedge SYSTEMCLOCK) begin
+        if (reset) begin
+            gpio_led <= 7'b1111;
+            throb_counter <= 26'd0;
+        end else begin
+            gpio_led[1:0] <= gpio_switch[1:0];
+            gpio_led[2] <= gpio_switch[2] || gpio_switch[3];
+            if (throb_counter >= 26'd50_000_000) begin
+                gpio_led[3] <= !gpio_led[3]; 
+                throb_counter <= 26'd0;
+            end else begin
+                throb_counter <= throb_counter + 26'd1;
+            end
+        end
+    end
+
+endmodule