lib.fifo.AsyncFIFOBuffered: fix FFSynchronizer latency

[nmigen.git] / tests / test_lib_fifo.py

diff --git a/tests/test_lib_fifo.py b/tests/test_lib_fifo.py
index d276b3d17b4fa25da3231dd747da6deffc11236b..f2edf3022e9c4b35e266ecf3b9fa59f4a635d400 100644 (file)
--- a/tests/test_lib_fifo.py
+++ b/tests/test_lib_fifo.py
@@ -344,6 +344,10 @@ class AsyncFIFOSimCase(FHDLTestCase):
         fifo = AsyncFIFOBuffered(width=32, depth=9, r_domain="read", w_domain="write")
         self.check_async_fifo_level(fifo, fill_in=5, expected_level=5)
 
+    def test_async_buffered_fifo_level_only_three(self):
+        fifo = AsyncFIFOBuffered(width=32, depth=9, r_domain="read", w_domain="write")
+        self.check_async_fifo_level(fifo, fill_in=3, expected_level=3)
+
     def test_async_buffered_fifo_level_full(self):
         fifo = AsyncFIFOBuffered(width=32, depth=9, r_domain="read", w_domain="write")
         self.check_async_fifo_level(fifo, fill_in=10, expected_level=9)