diff --git a/Lib/YMF262-HAL/Inc/FakeGPIO.hpp b/Lib/YMF262-HAL/Inc/FakeGPIO.hpp
deleted file mode 100644
index a117976..0000000
--- a/Lib/YMF262-HAL/Inc/FakeGPIO.hpp
+++ /dev/null
@@ -1,19 +0,0 @@
-#ifndef FAKE_GPIO_HPP
-#define FAKE_GPIO_HPP
-
-
-#include <cstdint>
-#include "GPIO.hpp"
-
-struct FakeGpio {
-    void set_data_bus(uint8_t val){}
-    void set_a0(Port port){}
-    void set_a1(Bank address_bank){}
-    void set_cs(State state){}
-    void set_wr(State state){}
-    void set_ic(State state){}
-    void set_rd(State state){}
-    void delay_ticks(uint32_t n){}
-};
-
-#endif
\ No newline at end of file
diff --git a/Lib/YMF262-HAL/Inc/YMF262-HAL.h b/Lib/YMF262-HAL/Inc/YMF262-HAL.h
new file mode 100644
index 0000000..4bd6d14
--- /dev/null
+++ b/Lib/YMF262-HAL/Inc/YMF262-HAL.h
@@ -0,0 +1,20 @@
+#ifndef YMF262_HAL_H
+#define YMF262_HAL_H
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct YMF262_HAL_Handle YMF262_HAL_Handle;
+
+YMF262_HAL_Handle* YMF262_HAL_Create(uint32_t opl_clock, uint32_t cpu_clock);
+void YMF262_HAL_Destroy(YMF262_HAL_Handle* handle);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
\ No newline at end of file
diff --git a/Tests/FakeGPIO.hpp b/Tests/FakeGPIO.hpp
new file mode 100644
index 0000000..77d1871
--- /dev/null
+++ b/Tests/FakeGPIO.hpp
@@ -0,0 +1,22 @@
+#ifndef FAKE_GPIO_HPP
+#define FAKE_GPIO_HPP
+
+#include <cstdint>
+#include <vector>
+#include <string>
+#include "GPIO.hpp"
+
+struct FakeGpio {
+    std::vector<std::string> log;
+
+    void set_data_bus(uint8_t val) { log.push_back("data " + std::to_string(val)); }
+    void set_a0(Port port)         { log.push_back(port == Port::ADDRESS ? "a0 ADDR" : "a0 DATA"); }
+    void set_a1(Bank bank)         { log.push_back(bank == Bank::BANK_0 ? "a1 B0" : "a1 B1"); }
+    void set_cs(State s)           { log.push_back(s == State::ACTIVE ? "cs ON" : "cs OFF"); }
+    void set_wr(State s)           { log.push_back(s == State::ACTIVE ? "wr ON" : "wr OFF"); }
+    void set_ic(State s)           { log.push_back(s == State::ACTIVE ? "ic ON" : "ic OFF"); }
+    void set_rd(State s)           { log.push_back(s == State::ACTIVE ? "rd ON" : "rd OFF"); }
+    void delay_ticks(uint32_t n)   { log.push_back("delay " + std::to_string(n)); }
+};
+
+#endif
\ No newline at end of file