fix: values update

test/test.py

@@ -30,15 +30,24 @@ async def test_comprehensive_functionality(dut):
     # Test Frequency Selection (indirectly via `uo_out` observation)
     await send_uart_byte(dut, 0b00000001)  # Frequency byte, expect a unique pattern on `uo_out`
     await ClockCycles(dut.clk, 500)
-    initial_uo_out = dut.uo_out.value.integer
+
+    # Ensure `uo_out` does not contain 'x' or 'z' before accessing it
+    initial_uo_out = dut.uo_out.value
+    if "x" in str(initial_uo_out) or "z" in str(initial_uo_out):
+        dut._log.warning("uo_out contains unknown ('x') or high-impedance ('z') states after frequency selection command.")
+        await ClockCycles(dut.clk, 500)
+
+    initial_uo_out_int = dut.uo_out.value.integer
     await ClockCycles(dut.clk, 1000)
-    new_uo_out = dut.uo_out.value.integer
-    assert initial_uo_out != new_uo_out, "Expected frequency effect on uo_out"
+    new_uo_out_int = dut.uo_out.value.integer
+
+    assert initial_uo_out_int != new_uo_out_int, "Expected frequency effect on uo_out"
 
     # Test Waveform Selection (indirectly via `uo_out` pattern observation)
     await send_uart_byte(dut, 0b01000010)  # Waveform byte, expect square wave pattern
     await ClockCycles(dut.clk, 500)
-    wave_pattern_observed = any(dut.uo_out.value.integer != initial_uo_out for _ in range(10))
+
+    wave_pattern_observed = any(dut.uo_out.value.integer != initial_uo_out_int for _ in range(10))
     assert wave_pattern_observed, "Expected waveform pattern on uo_out"
 
     # Test ADSR Modulation (observe non-zero `uo_out` upper bits)