diff --git a/cores/esp8266/HardwareSerial.cpp b/cores/esp8266/HardwareSerial.cpp
index 3a29c6701..1e638b0a7 100644
--- a/cores/esp8266/HardwareSerial.cpp
+++ b/cores/esp8266/HardwareSerial.cpp
@@ -193,6 +193,18 @@ void ICACHE_FLASH_ATTR uart0_uninit(uart_t* uart)
     os_free(uart);
 }
 
+#define FUNC_U0CTS    4
+#define FUNC_U0RTS    4
+
+void ICACHE_FLASH_ATTR uart0_swap(uart_t* uart)
+{
+    PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTCK_U, FUNC_U0CTS);
+    PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, FUNC_U0RTS);
+    //SWAP PIN : U0TXD<==>U0RTS(MTDO, GPIO15) , U0RXD<==>U0CTS(MTCK, GPIO13)
+    SET_PERI_REG_MASK(0x3ff00028 , BIT2);
+    PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0TXD_U, FUNC_GPIO1);
+    PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0RXD_U, FUNC_GPIO3);
+}
 
 void ICACHE_FLASH_ATTR
 uart_ignore_char(char c)
@@ -251,6 +263,13 @@ void ICACHE_FLASH_ATTR HardwareSerial::end()
     _tx_buffer = 0;
 }
 
+void ICACHE_FLASH_ATTR HardwareSerial::swap()
+{
+    uart0_swap(_uart);
+    pinMode(1, INPUT);
+    pinMode(3, INPUT);
+}
+
 void ICACHE_FLASH_ATTR HardwareSerial::setDebugOutput(bool en)
 {
     uart_set_debug(en);
diff --git a/cores/esp8266/HardwareSerial.h b/cores/esp8266/HardwareSerial.h
index c934d9c58..143dd3061 100644
--- a/cores/esp8266/HardwareSerial.h
+++ b/cores/esp8266/HardwareSerial.h
@@ -69,6 +69,7 @@ public:
     void begin(unsigned long baud) { begin(baud, 0); }
     void begin(unsigned long, uint8_t);
     void end();
+    void swap();  //use GPIO13 and GPIO15 as RX and TX
     int available(void) override;
     int peek(void) override;
     int read(void) override;