diff --git a/.clang-format b/.clang-format
index 7427375..1e81119 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,6 +1,6 @@
 BasedOnStyle: Google
 IndentWidth: 4
-AlignConsecutiveMacros: AcrossEmptyLines
+AlignConsecutiveMacros: Consecutive
 AlignConsecutiveDeclarations: true
 AlignConsecutiveAssignments: true
 BreakBeforeBraces: Custom
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d2e25c..c8d3db4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,7 @@ set(TARGET_C_SOURCES
     "BSP/StdDriver/src/wwdt.c"
     "src/main.c"
     "src/nfc_impl.c"
+    "src/libc-hooks.c"
 )
 
 # Copy them from Makefile
diff --git a/include/FreeRTOSConfig.h b/include/FreeRTOSConfig.h
index d39cbc1..48b070b 100644
--- a/include/FreeRTOSConfig.h
+++ b/include/FreeRTOSConfig.h
@@ -56,7 +56,7 @@
 #define configQUEUE_REGISTRY_SIZE               8
 #define configUSE_QUEUE_SETS                    0
 #define configUSE_TIME_SLICING                  0
-#define configUSE_NEWLIB_REENTRANT              0
+#define configUSE_NEWLIB_REENTRANT              1 /* impure_ptr for each tasks */
 #define configENABLE_BACKWARD_COMPATIBILITY     0
 #define configNUM_THREAD_LOCAL_STORAGE_POINTERS 5
 
diff --git a/lib/FreeRTOS-Kernel b/lib/FreeRTOS-Kernel
index 09a2c0b..840214d 160000
--- a/lib/FreeRTOS-Kernel
+++ b/lib/FreeRTOS-Kernel
@@ -1 +1 @@
-Subproject commit 09a2c0b3247605eca9a0cdd8450b9d4a88389ab1
+Subproject commit 840214dc2981611509f9802f11d0b177dea164b7
diff --git a/lib/pn512/src/pn512.c b/lib/pn512/src/pn512.c
index 1239d73..74589e2 100644
--- a/lib/pn512/src/pn512.c
+++ b/lib/pn512/src/pn512.c
@@ -14,8 +14,8 @@
  */
 #define PN512_CMD_SOFT_RESET 0x0F
 
-#define PN512_REG_PAGE(x)    ((uint8_t)(x >> 0x08U))
-#define PN512_REG_ADDR(x)    ((uint8_t)(x & 0xFFU))
+#define PN512_REG_PAGE(x) ((uint8_t)(x >> 0x08U))
+#define PN512_REG_ADDR(x) ((uint8_t)(x & 0xFFU))
 
 /**
  * @brief Switch register page to the same page as
@@ -42,7 +42,7 @@ static pn512_ret_t pn512_switch_register_page(pn512_t *nfc, uint16_t reg) {
 
 /**
  * @brief Read a register, except FIFO register.
- * 
+ *
  * @param nfc: pointer to pn512_t struct
  * @param reg: 16bit register to be set, `PN512_REG_XXXX`
  * @param value: [OUT] value to be read
@@ -62,7 +62,7 @@ static pn512_ret_t pn512_read_register(pn512_t *nfc, uint16_t reg, uint8_t *valu
 
 /**
  * @brief Write a register, except FIFO register.
- * 
+ *
  * @param nfc: pointer to pn512_t struct
  * @param reg: 16bit register to be set, `PN512_REG_XXXX`
  * @param value: value to be written
@@ -81,7 +81,7 @@ static pn512_ret_t pn512_write_register(pn512_t *nfc, uint16_t reg, uint8_t valu
 }
 /**
  * @brief Soft reset PN512 by sending an SoftReset command.
- * 
+ *
  * @param nfc: pointer to pn512_t struct
  * @return pn512_ret_t: PN512_OK for success, PN512_FAIL for error.
  */
diff --git a/src/libc-hooks.c b/src/libc-hooks.c
new file mode 100644
index 0000000..0ec0a2f
--- /dev/null
+++ b/src/libc-hooks.c
@@ -0,0 +1,81 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <sys/stat.h>
+
+#include "NUC200Series.h"
+
+#include "FreeRTOS.h"
+#include "task.h"
+
+#define NEWLIB_HEAP_SIZE 0x400
+
+/* Static heap for newlib. */
+static uint8_t __attribute__((section(".heap"))) __attribute__((aligned(4))) s_heap[NEWLIB_HEAP_SIZE];
+
+size_t s_heap_sz = 0;
+
+int _getpid(void) {
+    return 0;
+}
+
+int _kill(int i, int j) {
+    return 0;
+}
+
+int _read(int fd, char *buf, int nbytes) {
+    return 0;
+}
+
+int _write(int fd, const void *buf, int nbytes) {
+    for(int i = 0; i < nbytes; i++) {
+        while(UART0->FSR & UART_FSR_TX_FULL_Msk) {
+            /* Wait for TX fifo available */
+        }
+        /* Write FIFO */
+        UART0->THR = ((uint8_t *)buf)[i];
+        i++;
+    }
+
+    return nbytes;
+}
+
+int _close(int file) {
+    return -1;
+}
+
+int _isatty(int file) {
+    return file <= 2;
+}
+
+int _fstat(int file, struct stat *st) {
+    st->st_mode = S_IFCHR;
+    return 0;
+}
+
+int _lseek(int file, int ptr, int dir){
+	return 0;
+}
+
+void *_sbrk(intptr_t count) {
+    void *ret, *ptr;
+
+    /* Note: current implementation does NOT support calling malloc from ISRs. */
+    if(xTaskGetSchedulerState() != taskSCHEDULER_NOT_STARTED) {
+        taskENTER_CRITICAL(); /* Freeze! */
+    }
+
+    ptr = s_heap + s_heap_sz;
+    if(s_heap_sz + count < NEWLIB_HEAP_SIZE) {
+        s_heap_sz += count;
+        ret = ptr;
+    }
+    else {
+        ret = (void *)-1;
+    }
+
+    if(xTaskGetSchedulerState() != taskSCHEDULER_NOT_STARTED) {
+        taskEXIT_CRITICAL();
+    }
+
+    return ret;
+}
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
index 9c7ec01..25baf0d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,6 +1,7 @@
-#include "NUC200Series.h"
+#include <stdio.h>
 
 #include "FreeRTOS.h"
+#include "NUC200Series.h"
 #include "task.h"
 
 /**
@@ -51,7 +52,7 @@ static void system_clock_config(void) {
      *  HCLK: 48MHz
      * SC0-2: 12MHz
      */
-    CLK->CLKDIV  = CLK_CLKDIV_ADC(4) | CLK_CLKDIV_UART(4) | CLK_CLKDIV_USB(1) | CLK_CLKDIV_HCLK(1);
+    CLK->CLKDIV  = CLK_CLKDIV_ADC(4) | CLK_CLKDIV_UART(1) | CLK_CLKDIV_USB(1) | CLK_CLKDIV_HCLK(1);
     CLK->CLKDIV1 = CLK_CLKDIV1_SC2(4) | CLK_CLKDIV1_SC1(4) | CLK_CLKDIV1_SC0(4);
 
     /**
@@ -74,18 +75,38 @@ static void system_clock_config(void) {
     CLK->CLKSEL2 = 0x200FFU; /* Reset value */
     CLK->CLKSEL3 = 0x3FU;    /* Reset value */
 
+    CLK_EnableModuleClock(UART0_MODULE);
+    CLK_EnableModuleClock(SPI0_MODULE);
+
     SystemCoreClockUpdate();
 }
 
 static void pinmux_config(void) {
     GPIO_SetMode(PA, BIT3, GPIO_PMD_OPEN_DRAIN); /* LED_GREEN */
     GPIO_SetMode(PA, BIT4, GPIO_PMD_OPEN_DRAIN); /* LED_RED   */
+
+    /* UART */
+    SYS->GPB_MFP &= ~(SYS_GPB_MFP_PB0_Msk | SYS_GPB_MFP_PB1_Msk);
+    SYS->GPB_MFP |= SYS_GPB_MFP_PB0_UART0_RXD | SYS_GPB_MFP_PB1_UART0_TXD;
+
+    /* NFC SPI Port PC0-3 */
+    SYS->GPC_MFP &= ~(SYS_GPC_MFP_PC0_Msk | SYS_GPC_MFP_PC1_Msk | SYS_GPC_MFP_PC2_Msk | SYS_GPC_MFP_PC3_Msk);
+    SYS->GPC_MFP |=
+        SYS_GPC_MFP_PC0_SPI0_SS0 | SYS_GPC_MFP_PC1_SPI0_CLK | SYS_GPC_MFP_PC2_SPI0_MISO0 | SYS_GPC_MFP_PC3_SPI0_MOSI0;
+
+    SYS->ALT_MFP &= ~(SYS_ALT_MFP_PC0_Msk | SYS_ALT_MFP_PC1_Msk | SYS_ALT_MFP_PC2_Msk | SYS_ALT_MFP_PC3_Msk);
+    SYS->ALT_MFP |=
+        SYS_ALT_MFP_PC0_SPI0_SS0 | SYS_ALT_MFP_PC1_SPI0_CLK | SYS_ALT_MFP_PC2_SPI0_MISO0 | SYS_ALT_MFP_PC3_SPI0_MOSI0;
+
+    /* NFC Reset and IRQ */
+
 }
 
 static void hello_task(void *pvParameters) {
     PA->DOUT ^= BIT4;
-    for(;;) {
+    for (;;) {
         PA->DOUT ^= BIT3 | BIT4;
+        printf("Hello?\r\n");
         vTaskDelay(pdMS_TO_TICKS(1000));
     }
 }
@@ -94,7 +115,15 @@ int main(int argc, const char *argv[]) {
     system_clock_config();
     pinmux_config();
 
-    xTaskCreate(hello_task, "HELLO", 128, NULL, 6, NULL);
+    UART_Open(UART0, 921600);
+
+    printf("UART0 opened for stdout operations.\r\n");
+
+    if(xTaskCreate(hello_task, "HELLO", 128, NULL, 6, NULL) != pdPASS) {
+        for(;;) {
+            //
+        }
+    }
 
     vTaskStartScheduler();
 
diff --git a/src/nfc_impl.c b/src/nfc_impl.c
index 1cb4704..2e9a4a0 100644
--- a/src/nfc_impl.c
+++ b/src/nfc_impl.c
@@ -60,7 +60,7 @@ pn512_ret_t pn512_poll_irq_ops(void *handle, uint32_t max_timeout) {
     /*
      * Poll for GPIO interrupt
      * (Get Semaphore)
-     * 
+     *
      */
 
     /* .. */
@@ -75,6 +75,4 @@ void SPI0_IRQHandler(void) {
 }
 
 /* <-- EXTI --> */
-void GPAB_IRQHandler(void) {
-    /* ??? Sasuga Nuvoton */
-}
\ No newline at end of file
+void GPAB_IRQHandler(void) { /* ??? Sasuga Nuvoton */ }
\ No newline at end of file