diff --git a/variants/m5stick_c/pins_arduino.h b/variants/m5stick_c/pins_arduino.h
index ef294e4845c..e4d73f6a2e3 100644
--- a/variants/m5stick_c/pins_arduino.h
+++ b/variants/m5stick_c/pins_arduino.h
@@ -14,6 +14,9 @@
 static const uint8_t TX = 1;
 static const uint8_t RX = 3;
 
+static const uint8_t TXD2 = 33;
+static const uint8_t RXD2 = 32;
+
 static const uint8_t SDA = 32;
 static const uint8_t SCL = 33;