diff --git a/Marlin/src/HAL/HC32/MarlinSerial.cpp b/Marlin/src/HAL/HC32/MarlinSerial.cpp
index 11d4abfab9..df8d39ae35 100644
--- a/Marlin/src/HAL/HC32/MarlinSerial.cpp
+++ b/Marlin/src/HAL/HC32/MarlinSerial.cpp
@@ -30,17 +30,17 @@
  * it would not make sense to parse G-Code from TMC responses
  */
 constexpr bool serial_handles_emergency(int port) {
-  return false
+  return (false
     #ifdef SERIAL_PORT
-         || (SERIAL_PORT) == port
+      || (SERIAL_PORT) == port
     #endif
     #ifdef SERIAL_PORT_2
-         || (SERIAL_PORT_2) == port
+      || (SERIAL_PORT_2) == port
     #endif
     #ifdef LCD_SERIAL_PORT
-         || (LCD_SERIAL_PORT) == port
+      || (LCD_SERIAL_PORT) == port
     #endif
-      ;
+  );
 }
 
 //
@@ -48,7 +48,7 @@ constexpr bool serial_handles_emergency(int port) {
 //
 
 // serial port where RX and TX use IRQs
-#define DEFINE_IRQ_SERIAL_MARLIN(name, n)      \
+#define DEFINE_IRQ_SERIAL_MARLIN(name, n)    \
   MSerialT name(serial_handles_emergency(n), \
                 &USART##n##_config,          \
                 BOARD_USART##n##_TX_PIN,     \
@@ -57,7 +57,7 @@ constexpr bool serial_handles_emergency(int port) {
 // serial port where RX uses DMA and TX uses IRQs
 // all serial ports use DMA1
 // since there are 4 USARTs and 4 DMA channels, we can use the USART number as the DMA channel
-#define DEFINE_DMA_SERIAL_MARLIN(name, n)      \
+#define DEFINE_DMA_SERIAL_MARLIN(name, n)    \
   MSerialT name(serial_handles_emergency(n), \
                 &USART##n##_config,          \
                 BOARD_USART##n##_TX_PIN,     \
@@ -67,12 +67,17 @@ constexpr bool serial_handles_emergency(int port) {
 
 #define DEFINE_SERIAL_MARLIN(name, n) TERN(SERIAL_DMA, DEFINE_DMA_SERIAL_MARLIN(name, n), DEFINE_IRQ_SERIAL_MARLIN(name, n))
 
-DEFINE_SERIAL_MARLIN(MSerial1, 1);
-DEFINE_SERIAL_MARLIN(MSerial2, 2);
-
-// TODO: remove this warning when SERIAL_DMA has been tested some more
-#if ENABLED(SERIAL_DMA)
-  #warning "SERIAL_DMA may be unstable on HC32F460."
+#if PINS_EXIST(BOARD_USART1_RX, BOARD_USART1_TX)
+  DEFINE_SERIAL_MARLIN(MSerial1, 1);
+#endif
+#if PINS_EXIST(BOARD_USART2_RX, BOARD_USART2_TX)
+  DEFINE_SERIAL_MARLIN(MSerial2, 2);
+#endif
+#if PINS_EXIST(BOARD_USART3_RX, BOARD_USART3_TX)
+  DEFINE_SERIAL_MARLIN(MSerial3, 3);
+#endif
+#if PINS_EXIST(BOARD_USART4_RX, BOARD_USART4_TX)
+  DEFINE_SERIAL_MARLIN(MSerial4, 4);
 #endif
 
 //
diff --git a/Marlin/src/HAL/HC32/MarlinSerial.h b/Marlin/src/HAL/HC32/MarlinSerial.h
index 1a97805a51..899e1bf2a7 100644
--- a/Marlin/src/HAL/HC32/MarlinSerial.h
+++ b/Marlin/src/HAL/HC32/MarlinSerial.h
@@ -92,3 +92,5 @@ typedef Serial1Class<MarlinSerial> MSerialT;
 
 extern MSerialT MSerial1;
 extern MSerialT MSerial2;
+extern MSerialT MSerial3;
+extern MSerialT MSerial4;
diff --git a/Marlin/src/HAL/HC32/MinSerial.cpp b/Marlin/src/HAL/HC32/MinSerial.cpp
index 93017ee0df..3475aca39d 100644
--- a/Marlin/src/HAL/HC32/MinSerial.cpp
+++ b/Marlin/src/HAL/HC32/MinSerial.cpp
@@ -33,7 +33,7 @@
 // Shared by both panic and PostMortem debugging
 //
 static void minserial_begin() {
-  #if !WITHIN(SERIAL_PORT, 1, 3)
+  #if !WITHIN(SERIAL_PORT, 1, 4)
     #warning "MinSerial requires a physical UART port for output."
     #warning "Disabling MinSerial because the used serial port is not a HW port."
   #else
diff --git a/Marlin/src/HAL/HC32/app_config.h b/Marlin/src/HAL/HC32/app_config.h
index b971903bba..2714887028 100644
--- a/Marlin/src/HAL/HC32/app_config.h
+++ b/Marlin/src/HAL/HC32/app_config.h
@@ -58,6 +58,9 @@
   #define USART_RX_DMA_SUPPORT 1
 #endif
 
+// SoftwareSerial uses STM32duino API compatibility mode
+#define SOFTWARE_SERIAL_STM32_API_COMPATIBILITY 1
+
 //
 // Misc.
 //
diff --git a/Marlin/src/HAL/HC32/inc/SanityCheck.h b/Marlin/src/HAL/HC32/inc/SanityCheck.h
index c6b3b221df..0698dc5aa4 100644
--- a/Marlin/src/HAL/HC32/inc/SanityCheck.h
+++ b/Marlin/src/HAL/HC32/inc/SanityCheck.h
@@ -43,8 +43,11 @@
   #error "FAST_PWM_FAN is not yet implemented for this platform."
 #endif
 
-#if !defined(HAVE_SW_SERIAL) && HAS_TMC_SW_SERIAL
-  #error "Missing SoftwareSerial implementation."
+// SoftwareSerial introduced in arduino core version 1.3.1
+#if ARDUINO_CORE_VERSION_INT < GET_VERSION_INT(1, 3, 1)
+  #if !defined(HAVE_SW_SERIAL) && HAS_TMC_SW_SERIAL
+    #error "Missing SoftwareSerial implementation."
+  #endif
 #endif
 
 #if ENABLED(SDCARD_EEPROM_EMULATION) && !HAS_MEDIA
diff --git a/Marlin/src/pins/hc32f4/pins_AQUILA_101.h b/Marlin/src/pins/hc32f4/pins_AQUILA_101.h
index dd8488de64..29e0656e40 100644
--- a/Marlin/src/pins/hc32f4/pins_AQUILA_101.h
+++ b/Marlin/src/pins/hc32f4/pins_AQUILA_101.h
@@ -222,10 +222,6 @@
 #define BOARD_USART2_TX_PIN                 PA9
 #define BOARD_USART2_RX_PIN                 PA15
 
-// Unused / Debug
-#define BOARD_USART3_TX_PIN                 PE5
-#define BOARD_USART3_RX_PIN                 PE4
-
 // Onboard LED (HIGH = off, LOW = on)
 #ifndef LED_BUILTIN
   #define LED_BUILTIN                       PA3
diff --git a/Marlin/src/pins/pins.h b/Marlin/src/pins/pins.h
index 4672c92e01..cac64ad677 100644
--- a/Marlin/src/pins/pins.h
+++ b/Marlin/src/pins/pins.h
@@ -925,9 +925,9 @@
 //
 
 #elif MB(AQUILA_V101)
-  #include "hc32f4/pins_AQUILA_101.h"               // HC32F460                             env:HC32F460C_aquila_101
+  #include "hc32f4/pins_AQUILA_101.h"               // HC32F460                             env:HC32F460C_aquila_101 env:HC32F460C_openhc32boot
 #elif MB(CREALITY_ENDER2P_V24S4)
-  #include "hc32f4/pins_CREALITY_ENDER2P_V24S4.h"   // HC32F460                             env:HC32F460C_e2p24s4
+  #include "hc32f4/pins_CREALITY_ENDER2P_V24S4.h"   // HC32F460                             env:HC32F460C_e2p24s4 env:HC32F460C_openhc32boot
 
 //
 // GD32 ARM Cortex-M3
diff --git a/ini/hc32.ini b/ini/hc32.ini
index 19baeda210..ee06fe9ecd 100644
--- a/ini/hc32.ini
+++ b/ini/hc32.ini
@@ -29,7 +29,7 @@
 [HC32F460_base]
 platform          = https://github.com/shadow578/platform-hc32f46x/archive/1.1.1.zip
 platform_packages = framework-hc32f46x-ddl@https://github.com/shadow578/framework-hc32f46x-ddl/archive/2.2.3.zip
-                    framework-arduino-hc32f46x@https://github.com/shadow578/framework-arduino-hc32f46x/archive/1.2.0.zip
+                    framework-arduino-hc32f46x@https://github.com/shadow578/framework-arduino-hc32f46x/archive/1.3.1.zip
 board             = generic_hc32f460
 build_src_filter  = ${common.default_src_filter} +<src/HAL/HC32> +<src/HAL/shared/backtrace>
 build_type        = release
@@ -80,7 +80,7 @@ board_upload.maximum_size = 524288
 [env:HC32F460C_aquila_101]
 extends = HC32F460C_base
 board_upload.offset_address = 0xC000  # Bootloader start address, as logged by the bootloader on boot
-board_build.boot_mode = secondary     # Save ~1.4k of flash by compiling as secondary firmware
+board_build.boot_mode = secondary     # Save ~1.4k of flash by compiling as secondary firmware (no ICG)
 
 #
 # Creality Ender 2 Pro v2.4.S4_170 (HC32f460kcta) (256K Flash, 192K RAM).
@@ -88,3 +88,27 @@ board_build.boot_mode = secondary     # Save ~1.4k of flash by compiling as seco
 [env:HC32F460C_e2p24s4]
 extends = HC32F460C_base
 board_upload.offset_address = 0x8000
+
+#
+# OpenHC32Boot (256K Flash).
+# This can be used with any HC32F460C printer, provided it has OpenHC32Boot installed.
+# see https://github.com/shadow578/OpenHC32Boot for more information
+#
+[env:HC32F460C_openhc32boot]
+extends = HC32F460C_base
+board_upload.offset_address = 0x4000
+board_build.boot_mode = secondary
+build_flags =
+  ${HC32F460C_base.build_flags}
+  -D CORE_DONT_RESTORE_DEFAULT_CLOCKS=1     # OpenHC32Boot doesn't mess with the clock settings, so we can skip clock restore in the core
+
+#
+# OpenHC32Boot (512K Flash)
+#
+[env:HC32F460E_openhc32boot]
+extends = HC32F460E_base
+board_upload.offset_address = 0x4000
+board_build.boot_mode = secondary
+build_flags =
+  ${HC32F460E_base.build_flags}
+  -D CORE_DONT_RESTORE_DEFAULT_CLOCKS=1