diff --git a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/ch32v20x_it.c b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/ch32v20x_it.c
index 517efd3..2ec8bc9 100644
--- a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/ch32v20x_it.c
+++ b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/ch32v20x_it.c
@@ -16,6 +16,7 @@
 #include "ch32v20x_it.h"
 #include "eth_driver.h"
 #include "CONFIG.h"
+#include "debug.h"
 
 /*********************************************************************
  * LOCAL FUNCTIONS
@@ -47,6 +48,16 @@ void NMI_Handler(void)
  */
 void HardFault_Handler(void)
 {
+    /* 诊断 (2026-08-13): 抓 RISC-V 异常现场, 定位 HardFault 源头
+       mcause: 5=Load访问错误 7=Store访问错误 2=非法指令 4/6=未对齐
+       mepc  : 异常指令 PC (用 .map 文件反查函数)
+       mtval : 错误访问地址 (Load/Store fault 时=野指针地址) */
+    uint32_t _mcause = 0, _mepc = 0, _mtval = 0;
+    __asm__ volatile("csrr %0, 0x342" : "=r"(_mcause));
+    __asm__ volatile("csrr %0, 0x341" : "=r"(_mepc));
+    __asm__ volatile("csrr %0, 0x343" : "=r"(_mtval));
+    PRINT("HARDFAULT: mcause=0x%08lx mepc=0x%08lx mtval=0x%08lx\n",
+          (unsigned long)_mcause, (unsigned long)_mepc, (unsigned long)_mtval);
     NVIC_SystemReset();
     while(1)
     {