1 Log调试¶
1.1 Hcpu没有log出来¶
1，menuconfig→ RTOS → RT-Thread Kernel → Kernel Device Object→uart1 is configured as uart1;
2，menuconfig → RTOS → RT-Thread Components → Utilities→Enable ulog is turned on;
TIPS: You can input “/” in menuconfig to search for “ulog”;
3,Whether the configuration of UART1 in pinmux.c is correctly set as UART1 configuration, commonly BSP_ENABLE_QSPI3 is enabled;，如下图：
1.2 Lcpu没有log出来¶
如下配置后， 依然没有打印，
1，menuconfig→ RTOS → RT-Thread Kernel → Kernel Device Object→uart3 is configured as uart3;
2，menuconfig → RTOS → RT-Thread Components → Utilities→Enable ulog is turned on;
3，Ensure that in hcpu, menuconfig→ RTOS → RT-Thread Kernel → Kernel Device Object→uart1 is not configured as uart3 here, otherwise there will be a conflict;.
4, Ensure that in pinmux.c, the mode configuration of PB45 and PB46 for UART3 is correct, default configuration is correct;，如下：
HAL_PIN_Set(PAD_PB45, USART3_TXD, PIN_NOPULL, 0); // USART3 TX/SPI3_INT
HAL_PIN_Set(PAD_PB46, USART3_RXD, PIN_PULLUP, 0); // USART3 RX
其他原因1:
The project V0.9.9\example\rt_driver\project\ec-lb551 is used, the ble thread is not started, resulting in Lcpu program not being loaded;，
解决方案:
Open the ble thread or call the function lcpu_power_on() separately; start the code of lcpu;.
其他原因2：
example\multicore\ipc_queue\
example\pm\coremark\
These projects require sending the command lcpu on in the HCPU console to start LCPU, after successful startup, the startup log can be seen on the LCPU console;
解决方案：
Under the corresponding project, there is a readme.txt file, you can refer to its content to send commands to open Lcpu;
1.3 代码中Print register;方法¶
Direct address read operation;:
static uint32_t pinmode19;
pinmode19= *(volatile uint32_t *)0x4004304c; //Read the value of register 0x4004304c;
uint32_t reg_printf= *(volatile uint32_t *)0x50016000; //Print the value of register 0x50016000;
rt_kprintf("0x50016000:0x%x\n",reg_printf);
Direct address write operation;：
#define _WWORD(reg,value) \
{ \
volatile uint32_t * p_reg=(uint32_t *) reg; \
*p_reg=value; \
}
_WWORD(0x40003050,0x200); //Write the value 0x00000200 to PA01 pinmux register;
Register definition read operation;：
rt_kprintf("hwp_hpsys_rcc->CFGR:0x%x\n",hwp_hpsys_rcc->CFGR);
uint32_t reg_printf= hwp_hpsys_rcc->CFGR; //Print register;
rt_kprintf("hwp_hpsys_rcc->CFGR:0x%x\n",reg_printf);
Register definition write operation;：
hwp_hpsys_rcc->CFGR = 0x40003050;//直接写值
MODIFY_REG(hwp_pmuc->LPSYS_SWR, PMUC_LPSYS_SWR_PSW_RET_Msk,
MAKE_REG_VAL(1, PMUC_LPSYS_SWR_PSW_RET_Msk, PMUC_LPSYS_SWR_PSW_RET_Pos)); //Only modify the value of PMUC_LPSYS_SWR_PSW_RET_Msk to 1, other places remain unchanged;；
1.4 Log定位死机方法¶
提示对方核crash
如下的log，提示LCPU crash后，是Hcpu主动触发的Assert，需要看LCPU死机在哪里
07-11 10:31:55:616 [351767] E/mw.sys ISR: LCPU crash
07-11 10:31:55:617 Assertion failed at function:debug_queue_rx_ind, line number:221 ,(0)
07-11 10:31:55:617 Previous ISR enable 0
说明：在双核开发时，当一边cpu已经死机，另一cpu其实是未知的，可能还会持续跑很长一段时间，会导致问题不容易发现，目前软件上设计成了一边cpu出现了已知的assert或者hardfaul的情况下，都会通知对方核，对方核收到后，会触发自身的assert，便于查找问题；
Assert行号提示
如下的log提示了，Assert发生在drv_io.c文件的517行
07-10 16:41:16:382 [572392] I/drv.lcd lcd_task: HW close
07-10 16:41:16:385 HAL assertion failed in file:drv_io.c, line number:517
07-10 16:41:16:388 Assertion failed at function:HAL_AssertFailed, line number:616 ,(0)
07-10 16:41:16:389 Previous ISR enable 1
对应drv_io.c文件的517行如下图：
RT_ASSERT(0);或者HAL_ASSERT(s_lcd_power > 0);括号内值为0（False）时，就会出现死机;
此处出现死机，代表s_lcd_power > 0为假（s_lcd_power没有大于0）
Log提示死机PC指针信息
如下Log，在出现hard fault情况下，此时的PC指针因为已经跳转异常中断HardFault_Handler或MemManage_Handler里面的rt_hw_mem_manage_exception或rt_hw_hard_fault_exception函数内了，连接上看到的PC指针可能已经不是第一死机现场，此时Log打印出来的PC等一系列地址，就是第一死机现场，可以用于恢复死机第一现场，如下表示死在PC0x0007ef00这个地址，可以通过编译出来的对应*.asm文件，查看为什么这条指令会死机，通常是访问的内存或者地址不可达，出现异常中断死机。
说明: 函数handle_exception中,变量saved_stack_frame、saved_stack_pointer和error_reason在出现以上异常死机时，也会存储如下Log内死机的堆栈、死机堆栈地址和死机的原因，可以对照源代码数据结构来分析死机原因。
06-24 15:48:41:031 sp: 0x200195c8
06-24 15:48:41:037 psr: 0x80000000
06-24 15:48:41:041 r00: 0x00000000
06-24 15:48:41:042 r01: 0x2001960c
06-24 15:48:41:043 r02: 0x00000010
06-24 15:48:41:044 r03: 0x0007ef00
06-24 15:48:41:045 r04: 0x00000000
06-24 15:48:41:046 r05: 0x00000010
06-24 15:48:41:046 r06: 0x00000000
06-24 15:48:41:047 r07: 0x00000010
06-24 15:48:41:047 r08: 0x2001960c
06-24 15:48:41:048 r09: 0x2001965c
06-24 15:48:41:049 r10: 0x60000000
06-24 15:48:41:049 r11: 0x00000000
06-24 15:48:41:050 r12: 0x200001cd
06-24 15:48:41:051 lr: 0x12064845
06-24 15:48:41:052 pc: 0x0007ef00
06-24 15:48:41:052 hard fault on thread: mbox
06-24 15:48:41:053
06-24 15:48:41:053 =====================
06-24 15:48:41:054 PSP: 0x20019534, MSP: 0x2001419c
06-24 15:48:41:055 ===================