diff --git a/libraries/SrcWrapper/inc/stm32_def.h b/libraries/SrcWrapper/inc/stm32_def.h
index 00c4c3762c..f952d55c2c 100644
--- a/libraries/SrcWrapper/inc/stm32_def.h
+++ b/libraries/SrcWrapper/inc/stm32_def.h
@@ -6,7 +6,7 @@
  * @brief STM32 core version number
  */
 #define STM32_CORE_VERSION_MAJOR    (0x02U) /*!< [31:24] major version */
-#define STM32_CORE_VERSION_MINOR    (0x08U) /*!< [23:16] minor version */
+#define STM32_CORE_VERSION_MINOR    (0x09U) /*!< [23:16] minor version */
 #define STM32_CORE_VERSION_PATCH    (0x00U) /*!< [15:8]  patch version */
 /*
  * Extra label for development:
@@ -14,7 +14,7 @@
  * [1-9]: release candidate
  * F[0-9]: development
  */
-#define STM32_CORE_VERSION_EXTRA    (0x00U) /*!< [7:0]  extra version */
+#define STM32_CORE_VERSION_EXTRA    (0xF0U) /*!< [7:0]  extra version */
 #define STM32_CORE_VERSION          ((STM32_CORE_VERSION_MAJOR << 24U)\
                                         |(STM32_CORE_VERSION_MINOR << 16U)\
                                         |(STM32_CORE_VERSION_PATCH << 8U )\
diff --git a/platform.txt b/platform.txt
index 3b60a337cf..0f64fc17a1 100644
--- a/platform.txt
+++ b/platform.txt
@@ -5,7 +5,7 @@
 # https://arduino.github.io/arduino-cli/latest/platform-specification/
 
 name=STM32 boards groups (Board to be selected from Tools submenu 'Board part number')
-version=2.8.0
+version=2.9.0-dev
 
 
 # Define variables used multiple times in platform file