diff --git a/M5StickCPlus_FactoryTest2022.ino b/M5StickCPlus_FactoryTest2022.ino
index 59ad858..499716a 100644
--- a/M5StickCPlus_FactoryTest2022.ino
+++ b/M5StickCPlus_FactoryTest2022.ino
@@ -554,26 +554,44 @@
     RTC_TimeTypeDef time;
     M5.Rtc.GetTime(&time);
 
-    Disbuff.setTextSize(4);
-    Disbuff.setCursor(6, 25);
-    Disbuff.setTextColor(TFT_WHITE);
+    // Disbuff.setTextSize(4);
+    // Disbuff.setCursor(6, 25);
+    // Disbuff.setTextColor(TFT_GREEN);
 
     while ((!M5.BtnA.isPressed()) && (!M5.BtnB.isPressed()))
     {
         Disbuff.fillRect(0, 0, 240, 135, Disbuff.color565(0, 0, 0));
         M5.Rtc.GetTime(&time);
         Disbuff.setTextSize(4);
-        Disbuff.setTextColor(TFT_WHITE);
+        Disbuff.setTextColor(TFT_GREENYELLOW);
         Disbuff.setCursor(25, 50);
         Disbuff.printf("%02d:%02d:%02d", time.Hours, time.Minutes, time.Seconds);
-        Disbuff.fillRect(0, 0, 240, 25, Disbuff.color565(20, 20, 20));
+        Disbuff.fillRect(0, 0, 240, 35, Disbuff.color565(20, 20, 20));
         Disbuff.setTextSize(2);
-        Disbuff.drawString("BMP8563 RTC Time", 26, 5, 1);
+        Disbuff.setTextColor(TFT_WHITE);
+        Disbuff.drawString("BMP8563 RTC Time", 26, 15, 1);
+        Disbuff.setTextSize(2);
+        Disbuff.setCursor(6, 90);
+        Disbuff.setTextColor(TFT_YELLOW);
+        Disbuff.println("Press B to sync RTC from NTP");
         Displaybuff();
         M5.update();
         checkAXPPress();
         delay(100);
     }
+    if (M5.BtnB.isPressed())
+    {
+        // RTC sync from NTP
+        // Wifi → NTP → update RTC → WifiOff
+        wifi_setup();
+        ntp_setup();
+        wifi_down();
+
+        Init_ESPNOW(); // ESPNOWの初期化
+
+        M5.update();
+        DisplayRTC(); // あまりよろしくないが、やっぱり時刻同期を確認したいので
+    }
     while ((M5.BtnA.isPressed()) || (M5.BtnB.isPressed()))
     {
         M5.update();
diff --git a/wifi.ino b/wifi.ino
new file mode 100644
index 0000000..9ff2a70
--- /dev/null
+++ b/wifi.ino
@@ -0,0 +1,84 @@
+#include <M5StickCPlus.h>
+#include <WiFi.h>
+
+const char *ssid = "miura2g";
+const char *password = "jikken2022";
+const char *ntpserver = "ntp.nict.jp";
+
+void wifi_setup()
+{
+    M5.Lcd.fillScreen(ORANGE);
+    M5.Lcd.setCursor(10, 50, 4);
+
+    WiFi.begin(ssid, password); // 接続開始
+    while (WiFi.status() != WL_CONNECTED)
+    { // 接続中...
+        M5.Beep.tone(2000);
+        delay(200);
+        M5.Beep.mute();
+        delay(300);
+        M5.Lcd.print(".");
+    }
+    // 接続完了！！
+    M5.Beep.tone(4000);
+    M5.Lcd.fillScreen(GREEN);
+    M5.Lcd.setCursor(0, 8, 4);
+    M5.Lcd.setTextColor(BLACK, GREEN);
+    M5.Lcd.print("  Wifi Connected!\n  ");
+    String gotip = WiFi.localIP().toString(); // m5デバイスのIPアドレス
+    M5.Lcd.println(gotip);
+
+    // MACアドレスを表示
+    uint8_t mac[6];
+    char macchar[100];
+    esp_read_mac(mac, ESP_MAC_WIFI_STA);
+    sprintf(macchar, "  %02X:%02X:%02X:%02X:%02X:%02X", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+    String macstr = macchar;
+    M5.Lcd.println(macstr);
+
+    delay(1500);
+    M5.Beep.mute();
+}
+void wifi_down()
+{
+    WiFi.disconnect();
+    WiFi.mode(WIFI_OFF);
+}
+
+struct tm localTime;
+void ntp_setup()
+{
+    configTime(9 * 3600, 0, ntpserver);
+
+    delay(1000);
+
+    while (localTime.tm_year < 80) {
+      getLocalTime(&localTime);
+      M5.Beep.tone(1000);
+        delay(200);
+        M5.Beep.mute();
+        delay(300);
+        M5.Lcd.print(".");
+    }
+    M5.Beep.tone(2000);
+
+    setRTCfromLT(localTime);
+}
+
+void setRTCfromLT(struct tm lt) {
+  RTC_DateTypeDef DateStruct;
+  DateStruct.Year = lt.tm_year + 1900;
+  DateStruct.Month = lt.tm_mon + 1;
+  DateStruct.Date = lt.tm_mday;
+  DateStruct.WeekDay = lt.tm_wday;
+  M5.Rtc.SetData(&DateStruct);
+
+  RTC_TimeTypeDef TimeStruct;
+  TimeStruct.Hours   = lt.tm_hour;
+  TimeStruct.Minutes = lt.tm_min;
+  TimeStruct.Seconds = lt.tm_sec+1;
+  M5.Rtc.SetTime(&TimeStruct);
+    M5.Lcd.print("  RTC updated!\n  ");
+    delay(1500);
+    M5.Beep.mute();
+}
\ No newline at end of file