diff --git a/include/serialport.h b/include/serialport.h
index 47d7d4a..16c6941 100644
--- a/include/serialport.h
+++ b/include/serialport.h
@@ -13,6 +13,6 @@ void serial_tty_init_i(NTTY* tty);
 void serial_tty_init_o(NTTY* tty);
 int serial_tty_read(NTTY* tty, char* buf, int nr);
 void serial_tty_write(NTTY* tty, char ch);
-void serial_tty_rcevbuf(NTTY* tty, char ch);
+void serial_tty_recvbuf(NTTY* tty, u32 ch);
 
 #endif
\ No newline at end of file
diff --git a/include/tty.h b/include/tty.h
index 0175db8..d770678 100644
--- a/include/tty.h
+++ b/include/tty.h
@@ -54,6 +54,9 @@ typedef struct n_tty
 	int driver_type; // 1-vga&kbd; 2-serial
 	void *input_buf;
 	void *output_buf;
+	void (*write)(struct n_tty *tty, char ch);
+	int (*read)(struct n_tty *tty, char* buf, int nr);
+	void (*recvbuf)(struct n_tty *tty, u32 ch);
 } NTTY;
 
 enum CSI_state
@@ -117,6 +120,7 @@ void vga_tty_select(NTTY *tty);
 
 void ps2_tty_init(NTTY *tty);
 int ps2_tty_read(NTTY *tty, char *buf, int nr);
+void ps2_tty_recvbuf(NTTY *tty, u32 key);
 
 #define CYCLE_SUB(head, tail, _max) ((head) <= (tail) ? (tail) - (head) : (tail) + (_max) - (head))
 #define NEXT(x, _max) (((x) + 1) % (_max))
diff --git a/kernel/keyboard.c b/kernel/keyboard.c
index 2dd3b3b..ed21907 100644
--- a/kernel/keyboard.c
+++ b/kernel/keyboard.c
@@ -33,7 +33,6 @@ static u8 mouse_data[MOUSE_IN_BYTES];
 static void set_leds();
 static void set_mouse_leds();
 static void kb_wait();
-static void ps2_push(NTTY *tty, u32 key);
 static void kbd_process(unsigned char scode);
 
 /*
@@ -128,7 +127,7 @@ void mouse_handler(int irq)
 			aux_state ^= (1 << i);
 			pack |= !!(aux_state & (1 << i)) ? MOUSEBTN_CLICK : MOUSEBTN_RELEASE;
 			pack |= (1 << i);
-			ps2_push(cur_ntty, pack);
+			cur_ntty->recvbuf(cur_ntty, pack);
 		}
 	}
 	pack = ISMOUSE | MOUSESCR;
@@ -136,13 +135,13 @@ void mouse_handler(int irq)
 	{
 		// actually it is 0x1
 		pack |= MOUSESCR_DOWN;
-		ps2_push(cur_ntty, pack);
+		cur_ntty->recvbuf(cur_ntty, pack);
 	}
 	else if ((signed char)mouse_data[3] < 0)
 	{
 		// actually it is 0xff
 		pack |= MOUSESCR_UP;
-		ps2_push(cur_ntty, pack);
+		cur_ntty->recvbuf(cur_ntty, pack);
 	}
 	for (i = 0; i < 2; i++)
 	{
@@ -154,7 +153,7 @@ void mouse_handler(int irq)
 				pack |= MOUSEPOS_NEG;
 			if (i == 1)
 				pack |= MOUSEPOS_XY;
-			ps2_push(cur_ntty, pack);
+			cur_ntty->recvbuf(cur_ntty, pack);
 		}
 	}
 	// kprintf("0x%02x 0x%02x 0x%02x 0x%02x\n", mouse_data[0], mouse_data[1], mouse_data[2], mouse_data[3]);
@@ -365,7 +364,7 @@ static void kbd_process(unsigned char scode)
 
 		// inputdriver_send_event(FALSE /*mouse*/, page, code, press, 0);
 		if (press)
-			ps2_push(cur_ntty, map_key(code));
+			cur_ntty->recvbuf(cur_ntty, map_key(code));
 	}
 
 	kbd_state = 0;
@@ -425,7 +424,7 @@ void ps2_tty_flush(NTTY *tty)
 	enable_int();
 }
 
-static void ps2_push(NTTY *tty, u32 key)
+void ps2_tty_recvbuf(NTTY *tty, u32 key)
 {
 	// kprintf("%x\n", key);
 	disable_int();
@@ -483,7 +482,7 @@ static void ps2_push(NTTY *tty, u32 key)
 		{
 		case '\r':
 		case '\n': // escape ENTER
-			vga_tty_write(tty, '\n');
+			tty->write(tty, '\n');
 			buf[kbd->tail] = '\n';
 			kbd->len++;
 			kbd->tail = NEXTKEY(kbd->tail);
@@ -493,7 +492,10 @@ static void ps2_push(NTTY *tty, u32 key)
 		case '\b':
 			if (kbd->len > kbd->readable)
 			{
-				vga_tty_backspace(tty);
+				// vga_tty_backspace(tty);
+				tty->write(tty, '\b');
+				tty->write(tty, ' ');
+				tty->write(tty, '\b');
 				kbd->len--;
 				kbd->tail = LASTKEY(kbd->tail);
 			}
@@ -504,7 +506,7 @@ static void ps2_push(NTTY *tty, u32 key)
 				return;
 			if (kbd->len == TTY_IN_BYTES - 1)
 				return; // leave one space for ctrl ascii
-			vga_tty_write(tty, key);
+			tty->write(tty, key);
 			buf[kbd->tail] = (u8)(key & 0xff);
 			// kprintf("%d %d %d", key & 0xff, kbd->tail, buf[kbd->tail]);
 			kbd->len++;
diff --git a/kernel/serialport.c b/kernel/serialport.c
index 5a3d39f..758327b 100644
--- a/kernel/serialport.c
+++ b/kernel/serialport.c
@@ -46,7 +46,7 @@ static void serial_buf_push(NTTY* tty, u32 key) {
 			sp->len++;
 			sp->tail = NEXTKEY(sp->tail);
 			sp->readable = CYCLE_SUB(sp->head, sp->tail, SERIAL_BUF_SIZE);
-         serial_tty_rcevbuf(tty, '\n');
+         	tty->recvbuf(tty, '\n');
 			break;
 		case '\b': case 127:
          key = '\b';
@@ -54,9 +54,9 @@ static void serial_buf_push(NTTY* tty, u32 key) {
 			{
 				sp->len--;
 				sp->tail = LASTKEY(sp->tail);
-            serial_tty_rcevbuf(tty, '\b');
-            serial_tty_rcevbuf(tty, ' ');
-            serial_tty_rcevbuf(tty, '\b');
+            	tty->recvbuf(tty, '\b');
+            	tty->recvbuf(tty, ' ');
+            	tty->recvbuf(tty, '\b');
 			}
 			break;
 
@@ -68,7 +68,7 @@ static void serial_buf_push(NTTY* tty, u32 key) {
 			buf[sp->tail] = (u8)(key & 0xff);
 			sp->len++;
 			sp->tail = NEXTKEY(sp->tail);
-         serial_tty_rcevbuf(tty, key & 0xff);
+         	tty->recvbuf(tty, key & 0xff);
 			break;
 		}
 }
@@ -102,8 +102,8 @@ void serial_tty_write(NTTY* tty, char ch) {
    write_serial(ch);
 }
 
-void serial_tty_rcevbuf(NTTY* tty, char ch) {
-   serial_tty_write(tty, ch);
+void serial_tty_recvbuf(NTTY* tty, u32 ch) {
+   tty->write(tty, ch & 0xff);
 }
 
 int init_serial() {
diff --git a/kernel/tty.c b/kernel/tty.c
index 2708e07..2bf888b 100644
--- a/kernel/tty.c
+++ b/kernel/tty.c
@@ -46,17 +46,23 @@ void init_tty_main()
 		tty->output_buf = (vga_buf*)K_PHY2LIN(do_kmalloc(sizeof(vga_buf)));
 		vga_tty_init(tty);
 		ps2_tty_init(tty);
+		tty->write = vga_tty_write;
+		tty->read = ps2_tty_read;
+		tty->recvbuf = ps2_tty_recvbuf;
 		ntty_table[i] = tty;
-		// kprintf("tty: %p, outbuf: %p\n", tty, tty->output_buf);
 	}
-	tty = (NTTY*)K_PHY2LIN(do_kmalloc(sizeof(NTTY)));
-	tty->driver_type = 2;
-	tty->input_buf = (serial_buf*)K_PHY2LIN(do_kmalloc(sizeof(serial_buf)));
-	// kprintf("tty: %p, outbuf: %p\n", tty, tty->input_buf);
-	tty->output_buf = NULL;
-	serial_tty_init_i(tty);
-	serial_tty_init_o(tty);
-	ntty_table[2] = tty;
+	for (int i = 2; i < 3; ++ i) {
+		tty = (NTTY*)K_PHY2LIN(do_kmalloc(sizeof(NTTY)));
+		tty->driver_type = 2;
+		tty->input_buf = (serial_buf*)K_PHY2LIN(do_kmalloc(sizeof(serial_buf)));
+		tty->output_buf = NULL;
+		serial_tty_init_i(tty);
+		serial_tty_init_o(tty);
+		tty->write = serial_tty_write;
+		tty->read = serial_tty_read;
+		tty->recvbuf = serial_tty_recvbuf;
+		ntty_table[2] = tty;
+	}
 	cur_ntty = ntty_table[0];
 	tty_ok = 1;
 	kprintf("TTY initialized\n");
@@ -72,7 +78,7 @@ void task_tty()
 	volatile char serial_input;
 	while (1)
 	{
-		// sys_yield();
+		yield();
 		// vga_tty_flush(cur_ntty);
 		// serial_input = read_serial();
 		// vga_tty_write(get_tty(2), serial_input);
@@ -119,5 +125,5 @@ void tty_write(NTTY *tty, char *buf, int len)
  *****************************************************************************/
 int tty_read(NTTY *tty, char *buf, int len)
 {
-	return ps2_tty_read(tty, buf, len);
+	return tty->read(tty, buf, len);
 }
\ No newline at end of file