diff --git a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
index ceecfa1..1d8858c 100644
--- a/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
+++ b/vd960DBN/BLE/OnlyUpdateApp_Peripheral/APP/peripheral_main.c
@@ -331,6 +331,23 @@ int main(void)
     HAL_Init();
 
     uart_init();
+
+    /* ===== 实验: 禁用 UART2 (Loop 口) 隔离测试 (2026-08-12) =====
+       目的: 验证 Loop MCU 数据/干扰是否导致复位循环 (RST_REASON 全 0 瞬态复位)
+       做法: USART2 关断 + PA3 脱离 UART 功能(上拉输入) — 等效软件断开 Loop
+       通过后删除此块; 另: 禁用后快照无帧入队, 同步验证快照 SPI 活动非诱因 */
+    {
+        GPIO_InitTypeDef gpio;
+        USART_ITConfig(USART2, USART_IT_RXNE, DISABLE);
+        USART_Cmd(USART2, DISABLE);
+        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
+        gpio.GPIO_Pin  = GPIO_Pin_3;
+        gpio.GPIO_Mode = GPIO_Mode_IPU;     /* PA3 脱离 UART2, 上拉输入 */
+        gpio.GPIO_Speed = GPIO_Speed_50MHz;
+        GPIO_Init(GPIOA, &gpio);
+        PRINT("ISOLATE: UART2 disabled (Loop isolation test)\n");
+    }
+
     TIM3_Init();
     TIM2_Init();