diff --git a/lib/miosix-kernel b/lib/miosix-kernel
index ce4f09ed..fef1263a 160000
--- a/lib/miosix-kernel
+++ b/lib/miosix-kernel
@@ -1 +1 @@
-Subproject commit ce4f09edb241165b6d086588471c9939daf97dbf
+Subproject commit fef1263a5df00d0f5d979e173c635d83be9388d1
diff --git a/meson.build b/meson.build
index d23e3b8c..6b9d3716 100644
--- a/meson.build
+++ b/meson.build
@@ -93,7 +93,8 @@ stm32f405_inc = ['platform/mcu/CMSIS/Include',
                  'platform/mcu/STM32F4xx/drivers',
                  'platform/mcu/STM32F4xx/drivers/usb']
 
-stm32f405_def = {'STM32F40_41xxx': '', 'HSE_VALUE':'8000000'}
+stm32f405_def = {'STM32F40_41xxx': '', 'HSE_VALUE':'8000000',
+                 '_POSIX_PRIORITY_SCHEDULING':''}
 
 ## MK22FN512
 
@@ -116,7 +117,7 @@ mk22fn512_inc = ['platform/mcu/CMSIS/Include',
                  'platform/mcu/CMSIS/Device/NXP/MK22FN512xxx12/Include',
                  'platform/mcu/MK22FN512xxx12/drivers']
 
-mk22fn512_def = {}
+mk22fn512_def = {'_POSIX_PRIORITY_SCHEDULING':''}
 
 ##
 ## Platform specializations
diff --git a/openrtx/src/bootstrap.c b/openrtx/src/bootstrap.c
deleted file mode 100644
index 1d241651..00000000
--- a/openrtx/src/bootstrap.c
+++ /dev/null
@@ -1,86 +0,0 @@
-/***************************************************************************
- *   Copyright (C) 2020 by Federico Izzo IU2NUO, Niccolò Izzo IU2KIN and   *
- *                         Silvano Seva IU2KWO                             *
- *                                                                         *
- *   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/>   *
- ***************************************************************************/
-
-#include <stdio.h>
-#include <app_cfg.h>
-#include <os.h>
-#include <hwconfig.h>
-
-/*
- * Entry point for application code, not in this translation unit.
- */
-int main(int argc, char *argv[]);
-
-/*
- * OS startup task, will call main() when all initialisations are done.
- */
-
-#ifdef RUN_TESTSUITE
-#define START_TSK_STKSIZE 4096/sizeof(CPU_STK)
-#else
-#define START_TSK_STKSIZE 512/sizeof(CPU_STK)
-#endif
-
-static OS_TCB  startTCB;
-static CPU_STK startStk[START_TSK_STKSIZE];
-static void startTask(void *arg);
-
-void systemBootstrap()
-{
-    OS_ERR err;
-
-    OSInit(&err);
-
-    OSTaskCreate((OS_TCB     *) &startTCB,
-                 (CPU_CHAR   *) " ",
-                 (OS_TASK_PTR ) startTask,
-                 (void       *) 0,
-                 (OS_PRIO     ) APP_CFG_TASK_START_PRIO,
-                 (CPU_STK    *) &startStk[0],
-                 (CPU_STK     ) startStk[START_TSK_STKSIZE / 10u],
-                 (CPU_STK_SIZE) START_TSK_STKSIZE,
-                 (OS_MSG_QTY  ) 0,
-                 (OS_TICK     ) 0,
-                 (void       *) 0,
-                 (OS_OPT      ) (OS_OPT_TASK_STK_CHK | OS_OPT_TASK_STK_CLR),
-                 (OS_ERR     *) &err);
-
-    OSStart(&err);
-
-    for(;;) ;
-}
-
-static void startTask(void* arg)
-{
-    (void) arg;
-
-    CPU_Init();
-
-    /* On ARM-based targets setup SysTick */
-    #ifdef __arm__
-    OS_CPU_SysTickInitFreq(SystemCoreClock);
-    #else
-    OS_CPU_SysTickInit();
-    #endif
-
-    /* Jump to application code */
-    main(0, NULL);
-
-    /* If main returns loop indefinitely */
-    for(;;) ;
-}
diff --git a/openrtx/src/threads.c b/openrtx/src/threads.c
index 66234a42..134cf7e0 100644
--- a/openrtx/src/threads.c
+++ b/openrtx/src/threads.c
@@ -20,6 +20,7 @@
 
 #include <hwconfig.h>
 #include <pthread.h>
+#include <sched.h>
 #include <ui.h>
 #include <state.h>
 #include <threads.h>
@@ -326,6 +327,14 @@ void create_threads()
 
     pthread_attr_init(&rtx_attr);
     pthread_attr_setstacksize(&rtx_attr, RTX_TASK_STKSIZE);
+
+    #ifdef _MIOSIX
+    // Max priority for RTX thread when running with miosix rtos
+    struct sched_param param;
+    param.sched_priority = sched_get_priority_max(0);
+    pthread_attr_setschedparam(&rtx_attr, &param);
+    #endif
+
     pthread_create(&rtx_thread, &rtx_attr, rtx_task, NULL);
 
     // Create UI thread