diff --git a/CMakeLists.txt b/CMakeLists.txt
index 90c17a2..3353425 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,6 +53,7 @@ set(TARGET_SOURCES
     "SDK/Drivers/PY32F0xx_HAL_Driver/Src/py32f0xx_ll_utils.c"
     "SDK/Drivers/CMSIS/Device/PY32F0xx/Source/gcc/startup_py32f030x6.s"
     "SDK/Drivers/CMSIS/Device/PY32F0xx/Source/system_py32f0xx.c"
+    "board/board.c"
     "src/py32f0xx_hal_msp.c"
     "src/py32f0xx_it.c"
     "src/app_syscalls.c"
@@ -67,6 +68,7 @@ set(TARGET_C_INCLUDES
     "SDK/Drivers/PY32F0xx_HAL_Driver/Inc"
     "SDK/Drivers/CMSIS/Include"
     "SDK/Drivers/CMSIS/Device/PY32F0xx/Include"
+    "board"
     "include"
 )
 
diff --git a/board/board.c b/board/board.c
new file mode 100644
index 0000000..230da30
--- /dev/null
+++ b/board/board.c
@@ -0,0 +1,16 @@
+#include "board.h"
+
+#include "py32f0xx_hal.h"
+
+void BOARD_InitBootPins(void) {
+    __HAL_RCC_GPIOB_CLK_ENABLE();
+
+    GPIO_InitTypeDef init = {
+        .Pin   = GPIO_PIN_0 | GPIO_PIN_1 | GPIO_PIN_3,
+        .Mode  = GPIO_MODE_OUTPUT_PP,
+        .Speed = GPIO_SPEED_FREQ_LOW,
+        .Pull  = GPIO_NOPULL,
+    };
+
+    HAL_GPIO_Init(GPIOB, &init);
+}
\ No newline at end of file
diff --git a/board/board.h b/board/board.h
new file mode 100644
index 0000000..3f5fdcf
--- /dev/null
+++ b/board/board.h
@@ -0,0 +1,14 @@
+#ifndef BOARD_H
+#define BOARD_H
+
+#define BOARD_LED_1_PORT GPIOB
+#define BOARD_LED_2_PORT GPIOB
+#define BOARD_LED_3_PORT GPIOB
+
+#define BOARD_LED_1_PIN GPIO_PIN_1
+#define BOARD_LED_2_PIN GPIO_PIN_0
+#define BOARD_LED_3_PIN_GPIO_PIN_3
+
+void BOARD_InitBootPins(void);
+
+#endif  // BOARD_H
diff --git a/src/main.c b/src/main.c
index a08acee..a79b4be 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,5 +1,8 @@
 #include <stdio.h>
 
+/* BSP */
+#include "board.h"
+
 /* App */
 #include "app_syscalls.h"
 #include "main.h"
@@ -9,11 +12,14 @@ UART_HandleTypeDef huart1;
 int main(void) {
     HAL_Init();
 
+    BOARD_InitBootPins();
+
     app_syscalls_init();
 
     printf("Hello world.\r\n");
 
     for (;;) {
-        /* -- */
+        HAL_GPIO_TogglePin(BOARD_LED_1_PORT, BOARD_LED_1_PIN);
+        HAL_Delay(500);
     }
 }
\ No newline at end of file