1 files changed, 23 insertions, 0 deletions
diff --git a/ice40/regressions/issue0203/ringosc.v b/ice40/regressions/issue0203/ringosc.v
new file mode 100644
index 0000000..6df8b0a
--- /dev/null
+++ b/ice40/regressions/issue0203/ringosc.v
@@ -0,0 +1,23 @@
+
+`timescale 1 ns / 1 ps
+`default_nettype none
+
+module top(output D1);
+
+  wire [1:0] buffers_in, buffers_out;
+  assign buffers_in = {buffers_out[0:0], ~buffers_out[1]};
+  SB_LUT4 #(
+          .LUT_INIT(16'd2)
+  ) buffers [1:0] (
+          .O(buffers_out),
+          .I0(buffers_in),
+          .I1(1'b0),
+          .I2(1'b0),
+          .I3(1'b0)
+  );
+
+  wire random = ~buffers_out[1];
+
+  assign D1 = random;
+
+endmodule // top