debug: 增加 Loopback_Test 硬件电气回环自检及对应的调试串口指令 'l'

Drivers/rf.c

@@ -355,3 +355,46 @@ void RF_DiagnosticMode(char choice)
         Uart_SendString("=== RF RX Test End ===\r\n");
     }
 }
+
+/**
+ * @brief 电气回环自检测试 (物理短路 P2.1 与 P3.6 自检)
+ * @details 用户通过短路 P2.1 和 P3.6 来实现 GPIO 的物理连通性自检
+ */
+void Loopback_Test(void)
+{
+    u16 match_count = 0;
+    u16 i;
+    
+    EAXFR = 1;
+    RF_SetMode(1); // 开启接收芯片
+    Delay_ms(100); 
+    
+    Uart_SendString("Starting RF Hardware Loopback Test (P2.1 -> P3.6)...\r\n");
+    Uart_SendString("Please use a metal tweezers to short-circuit P2.1 (Pin 22) and P3.6 (Pin 19)!\r\n");
+    
+    for (i = 0; i < 100; i++)
+    {
+        RF_TX_DAT = 1;
+        Delay_us(500);
+        if (RF_RX_DATA == 1) match_count++;
+        
+        RF_TX_DAT = 0;
+        Delay_us(500);
+        if (RF_RX_DATA == 0) match_count++;
+    }
+    
+    Uart_SendString("Loopback Match Count: ");
+    Uart_SendHex16(match_count);
+    Uart_SendString("/200\r\n");
+    
+    if (match_count > 150)
+    {
+        Uart_SendString("Result: PASS! Pin P2.1 and P3.6 are electrical connected successfully!\r\n");
+    }
+    else
+    {
+        Uart_SendString("Result: FAIL! GPIO coupling check failed. Short-circuit the pins and test again.\r\n");
+    }
+    
+    RF_SetMode(0); // 关断射频
+}

Drivers/rf.h

@@ -61,4 +61,9 @@ bit EV1527_Decode(u32 *out_addr, u8 *out_data);
  */
 void RF_DiagnosticMode(char choice);
 
+/**
+ * @brief 电气回环自检测试 (物理短路 P2.1 与 P3.6 自检)
+ */
+void Loopback_Test(void);
+
 #endif // __RF_H__