diff --git a/020_arduino.sh b/020_arduino.sh
index 33c170f..98f3101 100755
--- a/020_arduino.sh
+++ b/020_arduino.sh
@@ -4,7 +4,7 @@ ARDUINO_VERSION=1.8.13
 #ARDUINO_HOME=~/
 ARDUINO_HOME=/opt
 ARDUINO_DIR=${ARDUINO_HOME}/arduino-${ARDUINO_VERSION}/
-ARDUINO_TOOLS_DIR=${ARDUINO_TOOLS_DIR}
+ARDUINO_TOOLS_DIR=${ARDUINO_DIR}
 ADD_URLS=
 
 mkdir "${ARDUINO_TOOLS_DIR}"
@@ -18,7 +18,7 @@ wget -c https://downloads.arduino.cc/arduino-${ARDUINO_VERSION}-linux64.tar.xz &
 	tar xf /var/tmp/arduino-${ARDUINO_VERSION}-linux64.tar.xz
 
 usermod -a -G dialout "${USER}" && \
-apt install -y git python-serial
+apt install -y git python3-serial
 
 #https://raw.githubusercontent.com/espressif/arduino-esp32/master/package/package_esp32_index.template.json
 #http://arduino.esp8266.com/stable/package_esp8266com_index.json
@@ -28,20 +28,22 @@ apt install -y git python-serial
 
 # https://github.com/arduino/Arduino/wiki/Unofficial-list-of-3rd-party-boards-support-urls
 # Install ESP32 core
-ADD_URLS="${ADD_URLS},https://raw.githubusercontent.com/espressif/arduino-esp32/master/package/package_esp32_index.template.json"
+ADD_URLS="${ADD_URLS},https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json"
+#ADD_URLS="${ADD_URLS}, https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_dev_index.json"
 ${ARDUINO_DIR}/arduino \
 	--pref boardsmanager.additional.urls=${ADD_URLS} \
 	--save-prefs
 # arduino [--install-boards package name:platform architecture[:version]]
 ${ARDUINO_DIR}/arduino --install-boards esp32:esp32
 
+# ESP32-core from git 369MB
 mkdir -p ${ARDUINO_DIR}/hardware/espressif && \
 	cd ${ARDUINO_DIR}/hardware/espressif && \
 	git clone https://github.com/espressif/arduino-esp32.git esp32 && \
 	cd esp32 && \
 	git submodule update --init --recursive && \
-	cd esp32/tools/ && \
-	python get.py
+	cd tools/ && \
+	python3 get.py
 
 # Install ESP8266
 cd /var/tmp || exit