From 0ee7abe61cf8fba5aaea56c3bccb038144f52cc9 Mon Sep 17 00:00:00 2001
From: Elizabeth Esparza <esparzae083@gmail.com>
Date: Fri, 17 Jan 2025 12:07:37 -0600
Subject: [PATCH] feat: debug UART timing

---
 test/tb.v    |  6 +++---
 test/test.py | 10 ++++++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/test/tb.v b/test/tb.v
index fe60ddf..e169a14 100644
--- a/test/tb.v
+++ b/test/tb.v
@@ -4,7 +4,6 @@ module tb;
     reg clk;
     reg rst_n;
     reg rx;
-    wire [7:0] uo_out;
     wire [2:0] wave_select;
     wire white_noise_en;
 
@@ -13,7 +12,6 @@ module tb;
         .clk(clk),
         .rst_n(rst_n),
         .rx(rx),
-        .uo_out(uo_out),
         .wave_select(wave_select),
         .white_noise_en(white_noise_en)
     );
@@ -37,7 +35,7 @@ module tb;
         integer i;
         begin
             rx = 1; // Idle state
-            #(104167); // One bit time at 9600 baud
+            #(104167); // Wait for idle time
             rx = 0; // Start bit
             #(104167);
             for (i = 0; i < 8; i = i + 1) begin
@@ -55,8 +53,10 @@ module tb;
         #200;    // Wait for reset
         send_uart_byte(8'h54);  // 'T' - Triangle wave
         #200;
+        $display("Wave Select: %b, White Noise Enable: %b", wave_select, white_noise_en);
         send_uart_byte(8'h53);  // 'S' - Sawtooth wave
         #200;
+        $display("Wave Select: %b, White Noise Enable: %b", wave_select, white_noise_en);
         $finish;
     end
 endmodule
diff --git a/test/test.py b/test/test.py
index 8441262..b032d34 100644
--- a/test/test.py
+++ b/test/test.py
@@ -3,6 +3,7 @@
 from cocotb.triggers import Timer
 
 async def send_uart_byte(dut, byte):
+    """Send a single UART byte."""
     # Start bit
     dut.rx.value = 0
     await Timer(104167, units="ns")
@@ -16,6 +17,7 @@ async def send_uart_byte(dut, byte):
 
 @cocotb.test()
 async def test_uart_wave_selection(dut):
+    """Test UART commands for wave selection."""
     # Clock generation
     clock = Clock(dut.clk, 40, units="ns")  # 25 MHz
     cocotb.start_soon(clock.start())
@@ -33,3 +35,11 @@ async def test_uart_wave_selection(dut):
     await send_uart_byte(dut, 0x53)  # 'S' - Sawtooth wave
     await Timer(100, units="ns")
     assert dut.wave_select.value == 0b001, "Sawtooth wave selection failed"
+
+    await send_uart_byte(dut, 0x4E)  # 'N' - Enable white noise
+    await Timer(100, units="ns")
+    assert dut.white_noise_en.value == 1, "White noise enable failed"
+
+    await send_uart_byte(dut, 0x46)  # 'F' - Disable white noise
+    await Timer(100, units="ns")
+    assert dut.white_noise_en.value == 0, "White noise disable failed"