diff --git a/src/main.cpp b/src/main.cpp
index 715acc0..7f42cfe 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -30,6 +30,15 @@ void serial_dump_byte_array(byte *buffer, byte bufferSize);
 void printMsg(const String &s);
 void printMsg(unsigned long l);
 
+void oled_dump_byte_array(byte *buffer, byte bufferSize)
+{
+  for (byte i = 0; i < bufferSize; i++)
+  {
+    display.print(buffer[i] < 0x10 ? " 0" : " ");
+    display.print(buffer[i], HEX);
+  }
+}
+
 void setup()
 {
   Serial.begin(9600);
@@ -105,8 +114,16 @@ void loop()
   // UID is a unique four hex pairs, e.g. E6 67 2A 12
   Serial.print(F("Card UID:"));
   serial_dump_byte_array(mfrc522.uid.uidByte, mfrc522.uid.size);
+
+  display.clearDisplay();
+  display.setTextColor(WHITE);
+  display.setTextSize(1);
+  display.setCursor(0, 10);
   display.println("Card UID: ");
+  oled_dump_byte_array(mfrc522.uid.uidByte, mfrc522.uid.size);
   display.println();
+  display.display();
+
   // PICC type, e.g. "MIFARE 1K0"
   Serial.print(F("PICC type: "));
   MFRC522::PICC_Type piccType = mfrc522.PICC_GetType(mfrc522.uid.sak);