diff --git a/__admin/multidevices_write2.sh b/__admin/multidevices_write2.sh
new file mode 100755
index 0000000..50770d6
--- /dev/null
+++ b/__admin/multidevices_write2.sh
@@ -0,0 +1,29 @@
+#!/bin/bash
+
+source ../lib.sh
+
+BUILD_TOOL=$(lib_get_esptool_command)
+
+allports=$(lib_detect_allports)
+if [ -z "$allports" ]; then
+    lib_no_esp_device_message_and_exit
+fi
+echo "Detected ports:"
+echo "$allports"
+
+# allports に対して、1つずつ書き込んでいく
+
+# Define the paths to the firmware files
+BUILD_PATH="../FactoryTest/build/esp32.esp32.m5stack_stickc_plus2"
+BOOTLOADER_PATH="$BUILD_PATH/FactoryTest.ino.bootloader.bin"
+PARTITIONS_PATH="$BUILD_PATH/FactoryTest.ino.partitions.bin"
+FIRMWARE_PATH="$BUILD_PATH/FactoryTest.ino.bin"
+
+for port in ${allports} ; do
+  echo "Flashing port: $port"
+  $BUILD_TOOL --chip esp32 --port "$port" --baud 460800 write-flash -z \
+      0x1000 "$BOOTLOADER_PATH" \
+      0x8000 "$PARTITIONS_PATH" \
+      0x10000 "$FIRMWARE_PATH" && echo "Flashing completed."
+
+done
diff --git a/lib.sh b/lib.sh
index ad0b319..2ca7f59 100644
--- a/lib.sh
+++ b/lib.sh
@@ -96,6 +96,30 @@
     echo "$PORT"
 }
 
+lib_detect_allports() {
+    local OS_TYPE=$(uname -s)
+    case "$OS_TYPE" in
+        "Darwin")  # macOS
+            ls /dev/cu.usbserial* /dev/cu.usbmodem* /dev/cu.wchusbserial* 2>/dev/null
+            ;;
+        "Linux")   # Linux
+            ls /dev/ttyUSB* /dev/ttyACM* 2>/dev/null
+            ;;
+        "CYGWIN"*|"MINGW"*|"MSYS"*)  # Windows (Git Bash, Cygwin, etc.)
+            for num in {3..20}; do
+                if [ -e "/dev/ttyS$((num-1))" ]; then
+                    echo "COM$num"
+                fi
+            done
+            ;;
+        *)
+            echo "Unknown OS: $OS_TYPE"
+            echo "Please manually specify the port using PORT environment variable"
+            echo "Example: PORT=/dev/ttyUSB0 $0"
+            ;;
+    esac
+}
+
 lib_no_esp_device_message_and_exit(){
     echo "No ESP device found automatically."
     echo "Please connect your ESP device and ensure drivers are installed."