diff --git a/Marlin/src/HAL/STM32/HAL.cpp b/Marlin/src/HAL/STM32/HAL.cpp
index 37cfb576d1..c09592a564 100644
--- a/Marlin/src/HAL/STM32/HAL.cpp
+++ b/Marlin/src/HAL/STM32/HAL.cpp
@@ -23,6 +23,7 @@
 #if defined(ARDUINO_ARCH_STM32) && !defined(STM32GENERIC)
 
 #include "HAL.h"
+#include "usb_serial.h"
 
 #include "../../inc/MarlinConfig.h"
 #include "../shared/Delay.h"
@@ -79,6 +80,8 @@ void HAL_init() {
   #endif
 
   SetSoftwareSerialTimerInterruptPriority();
+
+  TERN_(EMERGENCY_PARSER, USB_Hook_init());
 }
 
 void HAL_clear_reset_source() { __HAL_RCC_CLEAR_RESET_FLAGS(); }
diff --git a/Marlin/src/HAL/STM32/HAL.h b/Marlin/src/HAL/STM32/HAL.h
index 4c64d95153..3319636704 100644
--- a/Marlin/src/HAL/STM32/HAL.h
+++ b/Marlin/src/HAL/STM32/HAL.h
@@ -30,6 +30,7 @@
 #include "../shared/HAL_SPI.h"
 #include "fastio.h"
 #include "watchdog.h"
+#include "MarlinSerial.h"
 
 #include "../../inc/MarlinConfigPre.h"
 
@@ -48,17 +49,17 @@
 #elif SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
 #elif SERIAL_PORT == 1
-  #define MYSERIAL0 Serial1
+  #define MYSERIAL0 MSerial1
 #elif SERIAL_PORT == 2
-  #define MYSERIAL0 Serial2
+  #define MYSERIAL0 MSerial2
 #elif SERIAL_PORT == 3
-  #define MYSERIAL0 Serial3
+  #define MYSERIAL0 MSerial3
 #elif SERIAL_PORT == 4
-  #define MYSERIAL0 Serial4
+  #define MYSERIAL0 MSerial4
 #elif SERIAL_PORT == 5
-  #define MYSERIAL0 Serial5
+  #define MYSERIAL0 MSerial5
 #elif SERIAL_PORT == 6
-  #define MYSERIAL0 Serial6
+  #define MYSERIAL0 MSerial6
 #else
   #error "SERIAL_PORT must be from -1 to 6. Please update your configuration."
 #endif
@@ -72,17 +73,17 @@
   #elif SERIAL_PORT_2 == -1
     #define MYSERIAL1 SerialUSB
   #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 Serial1
+    #define MYSERIAL1 MSerial1
   #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 Serial2
+    #define MYSERIAL1 MSerial2
   #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 Serial3
+    #define MYSERIAL1 MSerial3
   #elif SERIAL_PORT_2 == 4
-    #define MYSERIAL1 Serial4
+    #define MYSERIAL1 MSerial4
   #elif SERIAL_PORT_2 == 5
-    #define MYSERIAL1 Serial5
+    #define MYSERIAL1 MSerial5
   #elif SERIAL_PORT_2 == 6
-    #define MYSERIAL1 Serial6
+    #define MYSERIAL1 MSerial6
   #else
     #error "SERIAL_PORT_2 must be from -1 to 6. Please update your configuration."
   #endif
@@ -100,17 +101,17 @@
   #elif DGUS_SERIAL_PORT == -1
     #define DGUS_SERIAL SerialUSB
   #elif DGUS_SERIAL_PORT == 1
-    #define DGUS_SERIAL Serial1
+    #define DGUS_SERIAL MSerial1
   #elif DGUS_SERIAL_PORT == 2
-    #define DGUS_SERIAL Serial2
+    #define DGUS_SERIAL MSerial2
   #elif DGUS_SERIAL_PORT == 3
-    #define DGUS_SERIAL Serial3
+    #define DGUS_SERIAL MSerial3
   #elif DGUS_SERIAL_PORT == 4
-    #define DGUS_SERIAL Serial4
+    #define DGUS_SERIAL MSerial4
   #elif DGUS_SERIAL_PORT == 5
-    #define DGUS_SERIAL Serial5
+    #define DGUS_SERIAL MSerial5
   #elif DGUS_SERIAL_PORT == 6
-    #define DGUS_SERIAL Serial6
+    #define DGUS_SERIAL MSerial6
   #else
     #error "DGUS_SERIAL_PORT must be from -1 to 6. Please update your configuration."
   #endif
diff --git a/Marlin/src/HAL/STM32/MarlinSerial.cpp b/Marlin/src/HAL/STM32/MarlinSerial.cpp
new file mode 100644
index 0000000000..1961791e22
--- /dev/null
+++ b/Marlin/src/HAL/STM32/MarlinSerial.cpp
@@ -0,0 +1,80 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#if defined(ARDUINO_ARCH_STM32) && !defined(STM32GENERIC)
+
+#include "../../inc/MarlinConfig.h"
+#include "MarlinSerial.h"
+
+#if ENABLED(EMERGENCY_PARSER)
+  #include "../../feature/e_parser.h"
+#endif
+
+#define DECLARE_SERIAL_PORT(ser_num) \
+  void _rx_complete_irq_ ## ser_num (serial_t * obj); \
+  MarlinSerial MSerial ## ser_num (USART ## ser_num, &_rx_complete_irq_ ## ser_num); \
+  void _rx_complete_irq_ ## ser_num (serial_t * obj) { MSerial ## ser_num ._rx_complete_irq(obj); }
+
+#define DECLARE_SERIAL_PORT_EXP(ser_num) DECLARE_SERIAL_PORT(ser_num)
+
+#if defined(SERIAL_PORT) && SERIAL_PORT >= 0
+  DECLARE_SERIAL_PORT_EXP(SERIAL_PORT)
+#endif
+
+#if defined(SERIAL_PORT_2) && SERIAL_PORT_2 >= 0
+  DECLARE_SERIAL_PORT_EXP(SERIAL_PORT_2)
+#endif
+
+#if defined(DGUS_SERIAL_PORT) && DGUS_SERIAL_PORT >= 0
+  DECLARE_SERIAL_PORT_EXP(DGUS_SERIAL_PORT)
+#endif
+
+void MarlinSerial::begin(unsigned long baud, uint8_t config) {
+  HardwareSerial::begin(baud, config);
+  // replace the IRQ callback with the one we have defined
+  #if ENABLED(EMERGENCY_PARSER)
+    _serial.rx_callback = _rx_callback;
+  #endif
+}
+
+// This function is Copyright (c) 2006 Nicholas Zambetti.
+void MarlinSerial::_rx_complete_irq(serial_t *obj) {
+  // No Parity error, read byte and store it in the buffer if there is room
+  unsigned char c;
+
+  if (uart_getc(obj, &c) == 0) {
+
+    rx_buffer_index_t i = (unsigned int)(obj->rx_head + 1) % SERIAL_RX_BUFFER_SIZE;
+
+    // if we should be storing the received character into the location
+    // just before the tail (meaning that the head would advance to the
+    // current location of the tail), we're about to overflow the buffer
+    // and so we don't write the character or advance the head.
+    if (i != obj->rx_tail) {
+      obj->rx_buff[obj->rx_head] = c;
+      obj->rx_head = i;
+    }
+
+    #if ENABLED(EMERGENCY_PARSER)
+      emergency_parser.update(emergency_state, c);
+    #endif
+  }
+}
+
+#endif // ARDUINO_ARCH_STM32 && !STM32GENERIC
diff --git a/Marlin/src/HAL/STM32/MarlinSerial.h b/Marlin/src/HAL/STM32/MarlinSerial.h
new file mode 100644
index 0000000000..290fdce9ee
--- /dev/null
+++ b/Marlin/src/HAL/STM32/MarlinSerial.h
@@ -0,0 +1,54 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../inc/MarlinConfigPre.h"
+
+#if ENABLED(EMERGENCY_PARSER)
+  #include "../../feature/e_parser.h"
+#endif
+
+typedef void (*usart_rx_callback_t)(serial_t * obj);
+
+class MarlinSerial : public HardwareSerial {
+public:
+  MarlinSerial(void* peripheral, usart_rx_callback_t rx_callback) :
+      HardwareSerial(peripheral), _rx_callback(rx_callback)
+      #if ENABLED(EMERGENCY_PARSER)
+        , emergency_state(EmergencyParser::State::EP_RESET)
+      #endif
+  { }
+
+  void begin(unsigned long baud, uint8_t config);
+  inline void begin(unsigned long baud) { begin(baud, SERIAL_8N1); }
+
+  void _rx_complete_irq(serial_t* obj);
+
+protected:
+  usart_rx_callback_t _rx_callback;
+  #if ENABLED(EMERGENCY_PARSER)
+    EmergencyParser::State emergency_state;
+  #endif
+};
+
+extern MarlinSerial MSerial1;
+extern MarlinSerial MSerial2;
+extern MarlinSerial MSerial3;
+extern MarlinSerial MSerial4;
+extern MarlinSerial MSerial5;
diff --git a/Marlin/src/HAL/STM32/inc/SanityCheck.h b/Marlin/src/HAL/STM32/inc/SanityCheck.h
index 7734fc0e83..7236b7f4ed 100644
--- a/Marlin/src/HAL/STM32/inc/SanityCheck.h
+++ b/Marlin/src/HAL/STM32/inc/SanityCheck.h
@@ -28,10 +28,6 @@
 //  #error "SPINDLE_LASER_PWM_PIN must use SERVO0, SERVO1 or SERVO3 connector"
 //#endif
 
-#if ENABLED(EMERGENCY_PARSER)
-  #error "EMERGENCY_PARSER is not yet implemented for STM32. Disable EMERGENCY_PARSER to continue."
-#endif
-
 #if ENABLED(FAST_PWM_FAN)
   #error "FAST_PWM_FAN is not yet implemented for this platform."
 #endif
diff --git a/Marlin/src/HAL/STM32/usb_serial.cpp b/Marlin/src/HAL/STM32/usb_serial.cpp
new file mode 100644
index 0000000000..86c164cb93
--- /dev/null
+++ b/Marlin/src/HAL/STM32/usb_serial.cpp
@@ -0,0 +1,55 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#if defined(ARDUINO_ARCH_STM32) && !defined(STM32GENERIC)
+
+#include "../../inc/MarlinConfigPre.h"
+
+#if ENABLED(EMERGENCY_PARSER)
+
+#include "usb_serial.h"
+#include "../../feature/e_parser.h"
+
+EmergencyParser::State emergency_state = EmergencyParser::State::EP_RESET;
+
+int8_t (*USBD_CDC_Receive_original) (uint8_t *Buf, uint32_t *Len) = nullptr;
+
+static int8_t USBD_CDC_Receive_hook(uint8_t *Buf, uint32_t *Len) {
+  for (uint32_t i = 0; i < *Len; i++)
+    emergency_parser.update(emergency_state, Buf[i]);
+  return USBD_CDC_Receive_original(Buf, Len);
+}
+
+typedef struct _USBD_CDC_Itf {
+  int8_t (* Init)(void);
+  int8_t (* DeInit)(void);
+  int8_t (* Control)(uint8_t cmd, uint8_t *pbuf, uint16_t length);
+  int8_t (* Receive)(uint8_t *Buf, uint32_t *Len);
+  int8_t (* Transferred)(void);
+} USBD_CDC_ItfTypeDef;
+
+extern USBD_CDC_ItfTypeDef USBD_CDC_fops;
+
+void USB_Hook_init() {
+  USBD_CDC_Receive_original = USBD_CDC_fops.Receive;
+  USBD_CDC_fops.Receive = USBD_CDC_Receive_hook;
+}
+
+#endif // EMERGENCY_PARSER
+#endif // ARDUINO_ARCH_STM32 && !STM32GENERIC
diff --git a/Marlin/src/HAL/STM32/usb_serial.h b/Marlin/src/HAL/STM32/usb_serial.h
new file mode 100644
index 0000000000..4243683479
--- /dev/null
+++ b/Marlin/src/HAL/STM32/usb_serial.h
@@ -0,0 +1,21 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+void USB_Hook_init();