Added base GOWIN eda script

examples/GW1NSR-4C/RTL/toplevel.v

@@ -0,0 +1,23 @@
+module led_blink
+(
+    input  clk_i,
+    input  reset_n_i,
+    output led_o
+);
+
+    reg [23:0] counter;
+    reg        polarity;
+
+    always@(posedge clk_i) begin
+        if (!reset_n_i)
+            counter <= 24'h00000;
+        else
+            counter <= counter + 1'b1;
+
+        if (counter == 24'hFFFFF)
+            polarity <= ~polarity;
+    end
+
+    assign led_o = polarity;
+
+endmodule