diff --git a/BSP/Debug/debug.c b/BSP/Debug/debug.c
index 9eb432c..82c3df5 100644
--- a/BSP/Debug/debug.c
+++ b/BSP/Debug/debug.c
@@ -155,14 +155,14 @@ __attribute__((used)) int _write(int fd, char *buf, int size)
     for(i = 0; i < size; i++)
     {
 #if(DEBUG_UART == DEBUG_UART1)
-        while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET);
-        USART_SendData(USART1, *buf++);
+        while(USART_GetFlagStatus(USART1, USART_FLAG_TXE) == RESET);
+        USART_SendData(USART1, buf[i]);
 #elif(DEBUG_UART == DEBUG_UART2)
-        while(USART_GetFlagStatus(USART2, USART_FLAG_TC) == RESET);
-        USART_SendData(USART2, *buf++);
+        while(USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET);
+        USART_SendData(USART2, buf[i]);
 #elif(DEBUG_UART == DEBUG_UART3)
-        while(USART_GetFlagStatus(USART3, USART_FLAG_TC) == RESET);
-        USART_SendData(USART3, *buf++);
+        while(USART_GetFlagStatus(USART3, USART_FLAG_TXE) == RESET);
+        USART_SendData(USART3, buf[i]);
 #endif
     }
 
diff --git a/BSP/Ld/Link.ld b/BSP/Ld/Link.ld
index 09174c7..083e0e9 100644
--- a/BSP/Ld/Link.ld
+++ b/BSP/Ld/Link.ld
@@ -1,9 +1,12 @@
 ENTRY( _start )
 
+/* Configure heap and stack space reserved for application.
+ * Too low may cause standard library failed,
+ * too high may cause SRAM overflow.
+ * Collision may occur with heap when stack gets too deep.
+ */
 __stack_size = 2048;
-
-PROVIDE( _stack_size = __stack_size );
-
+__heap_size  = 2048;
 
 MEMORY
 {
@@ -150,27 +153,25 @@ SECTIONS
         *(.gnu.linkonce.b.*)		
         *(COMMON*)
         . = ALIGN(4);
-        PROVIDE( _ebss = .);
+        PROVIDE(_ebss = .);
     } >RAM
 
-    PROVIDE( _end = _ebss);
-    PROVIDE( end = . );
-
-    .heap :
+    .heap_stack :
     {
+        . = ALIGN(8);
+        PROVIDE(_end = .);
+        PROVIDE(end = . );
 
-    }
+        . = . + __heap_size;
+        . = ALIGN(8);
+        PROVIDE(_heap_end = .);
 
-    .stack ORIGIN(RAM) + LENGTH(RAM) - __stack_size :
-    {
-        PROVIDE( _heap_end = . );    
-        . = ALIGN(4);
-        PROVIDE(_susrstack = . );
         . = . + __stack_size;
-        PROVIDE( _eusrstack = .);
-    } >RAM 
+        . = ALIGN(8);
+    } >RAM
 
+
+    /* Place initial SP to the end of SRAM */
+    __stack_top = ORIGIN(RAM) + LENGTH(RAM);
+    PROVIDE(_eusrstack = __stack_top);
 }
-
-
-
diff --git a/include/board.h b/include/board.h
index 1f7acd4..0031a7c 100644
--- a/include/board.h
+++ b/include/board.h
@@ -1,4 +1,8 @@
 #ifndef BOARD_H
 #define BOARD_H
 
+void BOARD_IOMUX_Init(void);
+void BOARD_Peripheral_Init(void);
+void BOARD_SystemClock_Config(void);
+
 #endif
\ No newline at end of file
diff --git a/src/board.c b/src/board.c
index 518671d..280b066 100644
--- a/src/board.c
+++ b/src/board.c
@@ -1,5 +1,30 @@
 #include "ch32v30x_conf.h"
 
-void BOARD_LED_Init(void) {
-    
+/**
+ * @brief Initialize IOMUX.
+ * 
+ */
+void BOARD_IOMUX_Init(void) {
+    /* The official devkit (CH32V307V-R1-1v0)
+     * does not have any LEDs directly connected to the MCU,
+     * and does not have any buttons directly connected to the MCU either...
+     */
+}
+
+/**
+ * @brief Initialize on-board peripherals.
+ * 
+ */
+void BOARD_Peripheral_Init(void) {
+}
+
+/**
+ * @brief Configure system clock,
+ * If you are not satisfied with the default options.
+ * 
+ */
+void BOARD_SystemClock_Config(void) {
+
+    // After you are done playing with RCC...
+    SystemCoreClockUpdate();
 }
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
index 5e6a0da..863f4d5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -4,13 +4,25 @@
 
 #include "debug.h"
 
-int main(void) {
+#include "board.h"
 
+int main(void) {
+    /* Initialize board components. */
+    BOARD_SystemClock_Config();
+    BOARD_IOMUX_Init();
+    BOARD_Peripheral_Init();
+
+
+    /* Initialize UART for libc function calls. */
     USART_Printf_Init(115200);
+    Delay_Init(); /* Silly function, will be replaced next time. */
 
     printf("Hello world?\r\n");
 
+    uint32_t i = 0;
+
     for(;;) {
-        //
+        Delay_Ms(500);
+        printf("Dead loop @%lu\r\n", i++);
     }
 }