diff --git a/upload.sh b/upload.sh
index 0f4560f..d78f0b8 100755
--- a/upload.sh
+++ b/upload.sh
@@ -3,5 +3,9 @@
 #serial=`ls /dev/ | grep cu.usbserial`
 #echo ${serial}
 
-arduino-cli upload --fqbn esp32:esp32:m5stick-c -p COM3 "."
+serial=`arduino-cli board list | grep COM | awk '{print $1}'`
+
+echo ${serial}
+
+arduino-cli upload --fqbn esp32:esp32:m5stick-c -p ${serial} "."
 #arduino-cli upload --fqbn esp32:esp32:m5stick-c -p /dev/${serial} "."