CubeMX Configuration

Configure the STM32F407 project in STM32CubeMX with required peripherals (e.g., USART1 for console) and generate code using the Low-Layer (LL) drivers instead of HAL.

Code Modifications

1. Include RT-Thread Header In source files that use RT-Thread APIs, add:

   #include <rtthread.h>
   

2. Declare System Clock Function In main.h, declare the clock configuration funciton if not already present:

   extern void SystemClock_Config(void);
   

3. RT-Thread Configuration (rtconfig.h) Customize rtconfig.h to enable essential features:

   #ifndef __RTTHREAD_CFG_H__
   #define __RTTHREAD_CFG_H__
   
   #define RT_THREAD_PRIORITY_MAX      32
   #define RT_TICK_PER_SECOND          1000
   #define RT_ALIGN_SIZE               4
   #define RT_NAME_MAX                 8
   
   #define RT_USING_COMPONENTS_INIT
   #define RT_USING_USER_MAIN
   #define RT_MAIN_THREAD_STACK_SIZE   1024
   
   #define RT_DEBUG
   #define RT_DEBUG_INIT               1
   
   #define RT_USING_HOOK
   #define RT_USING_IDLE_HOOK
   
   #define RT_TIMER_THREAD_PRIO        4
   #define RT_TIMER_THREAD_STACK_SIZE  512
   
   #define RT_USING_SEMAPHORE
   #define RT_USING_MUTEX
   #define RT_USING_EVENT
   #define RT_USING_MAILBOX
   #define RT_USING_MESSAGEQUEUE
   
   #define RT_USING_HEAP
   #define RT_USING_SMALL_MEM
   #define RT_USING_TINY_SIZE
   
   #define RT_USING_CONSOLE
   #define RT_CONSOLEBUF_SIZE          128
   
   #include "finsh_config.h"
   
   #endif /* __RTTHREAD_CFG_H__ */
   

4. Board Initialization (board.c) Implement hardware-specific initialization:

   #include <rthw.h>
   #include <rtthread.h>
   #include "main.h"
   #include "usart.h"
   
   #if defined(RT_USING_USER_MAIN) && defined(RT_USING_HEAP)
   #define STM32_SRAM1_END    (0x20020000)
   
   #if defined(__CC_ARM) || defined(__CLANG_ARM)
   extern int Image$$RW_IRAM1$$ZI$$Limit;
   #define HEAP_BEGIN         ((void *)&Image$$RW_IRAM1$$ZI$$Limit)
   #endif
   #endif
   
   void SysTick_Handler(void)
   {
       rt_interrupt_enter();
       rt_tick_increase();
       rt_interrupt_leave();
   }
   
   void rt_hw_board_init(void)
   {
       LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_SYSCFG);
       LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
       NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);
   
       SystemClock_Config();
       SystemCoreClockUpdate();
   
       SysTick_Config(SystemCoreClock / RT_TICK_PER_SECOND);
   
   #ifdef RT_USING_COMPONENTS_INIT
       rt_components_board_init();
   #endif
   
   #if defined(RT_USING_USER_MAIN) && defined(RT_USING_HEAP)
       rt_system_heap_init((void *)HEAP_BEGIN, (void *)STM32_SRAM1_END);
   #endif
   }
   
   #ifdef RT_USING_CONSOLE
   #define CONSOLE_UART USART1
   extern rt_bool_t usart1_ready;
   extern struct rt_mutex uart_tx_mutex;
   extern rt_bool_t mutex_initialized;
   
   void rt_hw_console_output(const char *str)
   {
       rt_size_t len = rt_strlen(str);
   
       if (mutex_initialized)
           rt_mutex_take(&uart_tx_mutex, RT_WAITING_FOREVER);
   
       if (usart1_ready)
       {
           for (rt_size_t i = 0; i < len; i++)
           {
               if (str[i] == '\n')
               {
                   while (!LL_USART_IsActiveFlag_TXE(CONSOLE_UART));
                   LL_USART_TransmitData8(CONSOLE_UART, '\r');
               }
               while (!LL_USART_IsActiveFlag_TXE(CONSOLE_UART));
               LL_USART_TransmitData8(CONSOLE_UART, str[i]);
           }
       }
   
       if (mutex_initialized)
           rt_mutex_release(&uart_tx_mutex);
   }
   #endif
   
   #ifdef RT_USING_FINSH
   char rt_hw_console_getchar(void)
   {
       if (LL_USART_IsActiveFlag_RXNE(CONSOLE_UART))
           return (char)LL_USART_ReceiveData8(CONSOLE_UART);
       else
           rt_thread_mdelay(10);
       return -1;
   }
   #endif
   

5. USART Initialization Flag In usart.c, set a global flag after USART1 is fully initialized:

   rt_bool_t usart1_ready = RT_FALSE;
   // ... inside MX_USART1_UART_Init()
   usart1_ready = RT_TRUE;
   

   Similarly, initiailze and manage a mutex for thread-safe UART output if needed.

With these changes, RT-Thread Nano runs on STM32F407 using LL drivers, and FinSH shell becomes available over USART1.