diff --git a/Src/main.c b/Src/main.c
index bafbf93..d5d7d21 100644
--- a/Src/main.c
+++ b/Src/main.c
@@ -54,6 +54,10 @@ main ()
   OLED_ShowPrintf (0, 4, "Hello, 4Wo4rld!", OLED_FONT_SIXTEEN, OLED_LEFT_ROLL,
                    OLED_CLS);
 
+  P2M1 &= 0xFE; // P20为推挽输出
+  P2M0 |= 0x01;
+  P20 = 1; // P20为推挽输出
+
   OLED_ShowNum (4, 4, 123456789, 10, OLED_FONT_SIXTEEN, OLED_LEFT_ROLL,
                 OLED_SHOW);
 
@@ -66,7 +70,7 @@ main ()
 
       DelayMs (1000);
 
-      read_i = (int16_t)(INA226_ReadBusVoltage ()*1000);
+      read_i = (int16_t)(INA226_ReadBusVoltage () * 1000);
 
       OLED_ShowNum (4, 6, read_i, 10, OLED_FONT_SIXTEEN, OLED_LEFT_ROLL,
                     OLED_SHOW);