diff --git a/Tests/CMakeLists.txt b/Tests/CMakeLists.txt
new file mode 100644
index 0000000..bfbc93c
--- /dev/null
+++ b/Tests/CMakeLists.txt
@@ -0,0 +1,25 @@
+cmake_minimum_required(VERSION 3.22)
+project(YMF262_Tests CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+include(FetchContent)
+FetchContent_Declare(
+    googletest
+    GIT_REPOSITORY https://github.com/google/googletest.git
+    GIT_TAG        v1.15.2
+)
+FetchContent_MakeAvailable(googletest)
+
+add_executable(run_tests test_write.cpp)
+
+target_include_directories(run_tests PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}/../Lib/YMF262-HAL/Inc
+    ${CMAKE_CURRENT_SOURCE_DIR}
+)
+
+target_link_libraries(run_tests PRIVATE gtest_main)
+
+include(GoogleTest)
+gtest_discover_tests(run_tests)
\ No newline at end of file
diff --git a/Tests/test_write.cpp b/Tests/test_write.cpp
new file mode 100644
index 0000000..5c69a13
--- /dev/null
+++ b/Tests/test_write.cpp
@@ -0,0 +1,19 @@
+#include <gtest/gtest.h>
+#include "YMF262-HAL.hpp"
+#include "FakeGPIO.hpp"
+
+TEST(YMF262Write, FazDoisCiclos) {
+    FakeGpio fake;
+    YMF262_HAL<FakeGpio> hal(fake, 14318000, 216000000);
+
+    hal.write(Bank::BANK_0, 0x40, 0x20);
+
+    // imprime o que foi registrado (pra você VER a coreografia)
+    for (const auto& linha : fake.log) {
+        std::cout << linha << "\n";
+    }
+
+    // verificações básicas: o primeiro ciclo é endereço, o barramento recebeu 0x40 (64)
+    EXPECT_EQ(fake.log.front(), "a0 ADDR");        // começou em modo endereço
+    EXPECT_FALSE(fake.log.empty());                 // anotou algo
+}
\ No newline at end of file