diff --git a/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.c b/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.c
index fb308a59..20d8dc5b 100644
--- a/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.c
+++ b/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.c
@@ -396,6 +396,16 @@ void LCD_Clear(uint16_t Color)
     }
 }
 
+void LCD_ClearRect(uint16_t Color, uint16_t x, uint16_t y, uint16_t width, uint16_t height)
+{
+    LCD_Address_Set(x, y, width, height);
+    for(uint16_t i=0; i<max_width; i++) {
+        for (uint16_t j=0; j<max_height; j++) {
+            LCD_WR_DATA(Color);
+        }
+    }
+}
+
 void LCD_ShowChinese(uint16_t x, uint16_t y, uint8_t index, uint16_t color)    
 {
     const uint8_t *p = (uint8_t*) &(Hzk[index*2][0]);
diff --git a/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.h b/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.h
index e0409141..9a748c6c 100644
--- a/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.h
+++ b/board/Sipeed_LonganNano/BSP/Hardware/lcd/lcd.h
@@ -61,6 +61,7 @@ void LCD_Address_Set(uint16_t x1, uint16_t y1, uint16_t x2,uint16_t y2);
 void LCD_SetDisplayMode(lcd_display_mode_t m);
 
 void LCD_Clear(uint16_t Color);
+void LCD_ClearRect(uint16_t Color, uint16_t x, uint16_t y, uint16_t width, uint16_t height);
 void LCD_ShowChinese(uint16_t x,uint16_t y,uint8_t index,uint16_t color);
 void LCD_DrawPoint(uint16_t x,uint16_t y,uint16_t color);
 void LCD_Fill(uint16_t xsta,uint16_t ysta,uint16_t xend,uint16_t yend,uint16_t color);
diff --git a/board/Sipeed_LonganNano/eclipse/nRF24L01/main.c b/board/Sipeed_LonganNano/eclipse/nRF24L01/main.c
index 67ade206..003acbfe 100644
--- a/board/Sipeed_LonganNano/eclipse/nRF24L01/main.c
+++ b/board/Sipeed_LonganNano/eclipse/nRF24L01/main.c
@@ -1,38 +1,6 @@
 #include "mcu_init.h"
 #include "tos_k.h"
-#include "lcd.h"
 
-#define LCD_TASK_SIZE 1024
-k_task_t lcd_handle;
-uint8_t lcd_stk[LCD_TASK_SIZE];
-
-
-void task_lcd(void *arg)
-{
-    uint16_t color_table[] = { WHITE, BLUE, RED, GREEN, CYAN, YELLOW, GRAY};
-
-    for(int i=0; ; i++) {
-        LCD_SetDisplayMode((i % 2) ? LCD_DISPMODE_HORIZONTAL_MIRROR : LCD_DISPMODE_HORIZONTAL);
-        LCD_Clear(BLACK);
-
-        uint16_t color = color_table[i % (sizeof(color_table)/sizeof(uint16_t))];
-
-
-        LCD_ShowChinese(50,       16, 0, color);
-        LCD_ShowChinese(50+16+28, 16, 1, color);
-
-        for(int j=0; j<6; j++) {
-            LCD_ShowChinese(22+j*20, 48, j+2, color);
-        }
-
-        tos_task_delay(1000);
-        LCD_Clear(BLACK);
-
-        LCD_ShowString(24, 32, "TencentOS tiny", color);
-
-        tos_task_delay(1000);
-    }
-}
 
 void nrf24l01_init();
 
@@ -45,8 +13,6 @@ void main(void) {
 
     nrf24l01_init();
 
-    tos_task_create(&lcd_handle,     "lcd", task_lcd, NULL, 7,   lcd_stk,   LCD_TASK_SIZE, 0);
-
     tos_knl_start();
 
 die:
diff --git a/board/Sipeed_LonganNano/eclipse/nRF24L01/nrf24.c b/board/Sipeed_LonganNano/eclipse/nRF24L01/nrf24.c
index 2d7ed718..bb9823d4 100644
--- a/board/Sipeed_LonganNano/eclipse/nRF24L01/nrf24.c
+++ b/board/Sipeed_LonganNano/eclipse/nRF24L01/nrf24.c
@@ -4,11 +4,13 @@
 #include "stdlib.h"
 #include "gd32vf103_gpio.h"
 #include "nrf24l01_gd32v_hal.h"
+#include "lcd.h"
 
 #define USE_SPI1
 
-extern k_sem_t sem_led;
 k_sem_t sem_nrf;
+k_sem_t sem_led;
+k_mutex_t mutex_lcd;
 
 #define TASK_SIZE (8*1024)
 k_task_t task_nrf24_handle;
@@ -19,6 +21,11 @@ k_task_t led_handle;
 uint8_t led_stk[LED_TASK_SIZE];
 
 
+#define LCD_TASK_SIZE 1024
+k_task_t lcd_handle;
+uint8_t lcd_stk[LCD_TASK_SIZE];
+
+
 #define CE_GPIO_PORT    GPIOA
 #define CE_PIN          GPIO_PIN_3
 #define CSN_GPIO_PORT   GPIOB
@@ -28,30 +35,13 @@ uint8_t led_stk[LED_TASK_SIZE];
 
 void task_nrf24();
 
-
-
-k_sem_t sem_led;
-
-typedef struct {
-    int port;
-    int pin;
-} Led_t;
-
-Led_t leds[] = {
-        { LEDR_GPIO_PORT, LEDR_PIN },
-        { LEDG_GPIO_PORT, LEDG_PIN },
-        { LEDB_GPIO_PORT, LEDB_PIN }
-};
-
+char lcd_buf[64];
 
 void task_led(void *arg)
 {
     int task_cnt1 = 0;
     while (1) {
-        //printf("hello world from %s cnt: %d\n", __func__, task_cnt1++);
-
         tos_sem_pend(&sem_led, ~0);
-
         gpio_bit_reset(LEDB_GPIO_PORT, LEDB_PIN);
         tos_task_delay(50);
         gpio_bit_set(LEDB_GPIO_PORT, LEDB_PIN);
@@ -59,6 +49,24 @@ void task_led(void *arg)
 }
 
 
+void task_lcd(void *arg)
+{
+    strcpy(lcd_buf, "initializing...");
+    LCD_SetDisplayMode(LCD_DISPMODE_HORIZONTAL_MIRROR);
+    LCD_Clear(BLACK);
+    const uint16_t x = 0;
+    const uint16_t y = 32;
+    uint8_t oldlen = strlen(lcd_buf);
+    for(int i=0; ; i++) {
+        tos_mutex_pend(&mutex_lcd);
+        uint8_t newlen = strlen(lcd_buf);
+        if(newlen < oldlen) {
+            LCD_Clear(BLACK);
+        }
+        oldlen = newlen;
+        LCD_ShowString(x, y, lcd_buf, CYAN);
+    }
+}
 
 void nrf24l01_init() {
     rcu_periph_clock_enable(RCU_GPIOA);
@@ -128,8 +136,10 @@ void nrf24l01_init() {
 
     tos_sem_create(&sem_nrf, 1);
     tos_sem_create(&sem_led, 1);
+    tos_mutex_create(&mutex_lcd);
     tos_task_create(&task_nrf24_handle, "task_nrf24",   task_nrf24,     NULL, 5, task_nrf24_stk, TASK_SIZE,     0);
     tos_task_create(&led_handle,        "led",          task_led,       NULL, 6, led_stk,        LED_TASK_SIZE, 0);
+    tos_task_create(&lcd_handle,        "lcd",          task_lcd,       NULL, 7, lcd_stk,        LCD_TASK_SIZE, 0);
 }
 
 void EXTI5_9_IRQHandler(void)
@@ -216,6 +226,8 @@ void test_nrf24l01_irq_rx()
 
         tos_sem_post(&sem_led);
 
+        strncpy(lcd_buf, buf, len);
+        tos_mutex_post(&mutex_lcd);
         printf("received %u bytes from pipe %u: ", len, pipe);
 
         for(int i=0; i<len; i++) {
@@ -252,7 +264,8 @@ void test_nrf24l01_rx() {
         nrf_poll_read_payload(buf, &len, &pipe);
 
         tos_sem_post(&sem_led);
-
+        strncpy(lcd_buf, buf, len);
+        tos_mutex_post(&mutex_lcd);
         printf("received %u bytes from pipe %u: ", len, pipe);
 
         for(int i=0; i<len; i++) {