diff --git a/include/tftlcd.h b/include/tftlcd.h
index 669ccd3..3f9d71f 100644
--- a/include/tftlcd.h
+++ b/include/tftlcd.h
@@ -105,7 +105,10 @@ typedef unsigned char uchar;
 
 void LCD_RESET();
 void LCD_Init();
-void LCD_S_XY(uint16_t x, uint16_t y);
-void LCD_S_Rec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye);
-void LCD_D_Point(uint16_t x, uint16_t y, uint16_t color);
-void LCD_Clear(uint16_t color);
\ No newline at end of file
+void LCD_SetColor(uint16_t color);
+void LCD_SetBackColor(uint16_t color);
+void LCD_SetXY(uint16_t x, uint16_t y);
+void LCD_SetRec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye);
+void LCD_DrawPoint(uint16_t x, uint16_t y, uint16_t color);
+void LCD_Clear(uint16_t color);
+void LCD_ShowChar(uint16_t x, uint16_t y, uint8_t num, uint8_t size, uint8_t mode);
diff --git a/src/tftlcd.c b/src/tftlcd.c
index fee2e9a..7fe1be3 100644
--- a/src/tftlcd.c
+++ b/src/tftlcd.c
@@ -1,9 +1,10 @@
+#include "font.h"
 #include "systick.h"
 #include "tftlcd.h"
 
-// 画笔颜色 背景颜色
-unsigned int POINT_COLOR = 0x0000, BACK_COLOR = 0xFFFF;
-unsigned int DeviceCode;
+uint16_t PEN_COLOR = 0x0000;   // 画笔颜色
+uint16_t BACK_COLOR = 0xFFFF;  // 背景颜色
+uint16_t DeviceCode;           // 设备模式
 
 void LCD_RESET() {
     LCD_RST_CLR;
@@ -204,16 +205,20 @@ void LCD_Init() {
     LCD_WR_REG(0x29);  // Display on
 
     LCD_BL_CLR;  // Back Light On
-    LCD_Clear(WHITE);
+    LCD_Clear(BACK_COLOR);
 }
 
-void LCD_S_XY(uint16_t x, uint16_t y) {
+void LCD_SetColor(uint16_t color) { PEN_COLOR = color; }
+
+void LCD_SetBackColor(uint16_t color) { BACK_COLOR = color; }
+
+void LCD_SetXY(uint16_t x, uint16_t y) {
     LCD_WR_REG_DATA_16BIT(LCD_PAGE_WR, x);
     LCD_WR_REG_DATA_16BIT(LCD_COL_WR, y);
 }
 
 // Set a rectangle area
-void LCD_S_Rec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye) {
+void LCD_SetRec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye) {
     LCD_WR_REG(LCD_PAGE_WR);
     LCD_WR_DATA_16BIT(xs);
     LCD_WR_DATA_16BIT(xe);
@@ -223,18 +228,60 @@ void LCD_S_Rec(uint16_t xs, uint16_t xe, uint16_t ys, uint16_t ye) {
     LCD_WR_DATA_16BIT(ye);
 }
 
-void LCD_D_Point(uint16_t x, uint16_t y, uint16_t color) {
-    LCD_S_XY(x, y);
+void LCD_DrawPoint(uint16_t x, uint16_t y, uint16_t color) {
+    LCD_SetXY(x, y);
     LCD_WR_REG_DATA_16BIT(LCD_RAM_WR, color);
 }
 
 void LCD_Clear(uint16_t color) {
-    LCD_S_Rec(0, LCD_W - 1, 0, LCD_H - 1);
+    LCD_SetRec(0, LCD_W - 1, 0, LCD_H - 1);
     LCD_WR_REG(LCD_RAM_WR);
     for (uint32_t i = 0; i < LCD_W * LCD_H; i++) LCD_WR_DATA_16BIT(color);
     // for (uint16_t i = 0; i < LCD_W; i++)
     //     for (uint16_t j = 0; j < LCD_H; j++) {
-    //         LCD_S_XY(i, j);
+    //         LCD_SetXY(i, j);
     //         LCD_WR_REG_DATA_16BIT(LCD_RAM_WR, color);
     //     }
 }
+
+/*
+    @brief Display a charactor on the position of (x,y)
+    @param x x of the lower left of the character
+    @param y y of the lower left of the character
+    @param sign the charactor
+    @param size size of the charactor, 12x06 or 16x08
+    @param mode 0: non-overlap, 1: overlap
+*/
+void LCD_ShowChar(uint16_t x, uint16_t y, uint8_t sign, uint8_t size, uint8_t mode) {
+    if (x > LCD_W || y > LCD_H) return;
+
+    uchar tmp;
+    uint16_t x0 = x;
+    const uchar *font;
+    if (size == 12) font = &asc2_1206[0][0];
+    else font = &asc2_1608[0][0];
+
+    sign = sign - ' ';
+    if (!mode) {  // non-overlap
+        for (uint16_t px = 0; px < size; px++) {
+            tmp = font[sign * size + px];
+            for (uint16_t py = 0; py < size / 2; py++) {
+                if (tmp & 0x01) LCD_DrawPoint(x, y, PEN_COLOR);
+                else LCD_DrawPoint(x, y, BACK_COLOR);
+                tmp >>= 1;
+                x++;
+            }
+            x = x0;
+            y++;
+        }
+    } else  // overlap
+    {
+        for (uint16_t px = 0; px < size; px++) {
+            tmp = font[sign * size + px];
+            for (uint16_t py = 0; py < size / 2; py++) {
+                if (tmp & 0x01) LCD_DrawPoint(x + py, y + px, PEN_COLOR);
+                tmp >>= 1;
+            }
+        }
+    }
+}