# BLUE ESC LED behavior **URL:** \ **Category:** Speed Controllers (ESCs)\ **Tags:** blue-esc\_retired\ **Created:** [December 15, 2015, 4:58am UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150 "2015-12-15T04:58:23Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![kr2-diving](https://avatars.discourse-cdn.com/v4/letter/k/ee59a6/32.png) [@kr2-diving](https://discuss.bluerobotics.com/u/kr2-diving)\ **Post date:** [December 15, 2015, 4:58am UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150/1 "2015-12-15T04:58:23Z")
I am looking to understand what the various states of the LEDs on the BLUE ESC signify. I am using the default version of the firmware (with I2C addressed updated only.) I understand the behavior can be modified in the firmware, but i am not looking to tinker with that… just curious what the default settings/states mean? Thanks, Ryan “KR2\_Diving” ---
**Author:** ![tciii](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/tciii/32/673_2.png) [@tciii](https://discuss.bluerobotics.com/u/tciii)\ **Post date:** [December 16, 2015, 2:24am UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150/2 "2015-12-16T02:24:02Z")
@Ryan, I have successfully communicated with my BlueESCs over the I2C signal control line. Each BlueESC is delivered with the default 0x29 hex address. You can load the Arduino I2C code, found in the [BlueESC Documentation](http://docs.bluerobotics.com/bluesc/), onto an Arduino Uno to communicate with the ESC at the default address. You can even use the send function in the Arduino IDE Serial Terminal to change the motor speeds from forward to reverse over the ESCs speed range. Make sure you include the [Blue Robotics Arduino\_I2C\_ESC library](https://github.com/bluerobotics/Arduino_I2C_ESC) into the Arduino IDE library before using the program. Since I have 6 BlueESCs I had to give each ESC a unique hex address. I started with 0x29 and ended with 0x2e. I loaded the ESC firmware files ([BlueESC Firmware (2015-07-09 a34f109)](http://docs.bluerobotics.com/blueesc/firmware/blueesc_firmware_2015-07-09_a34f109.zip)) for each unique hex address onto my PC and used the [ArduinoUSBLinker](https://github.com/c---/ArduinoUSBLinker) on the Arduino Uno and the [KKMulticopterTool](http://lazyzero.de/en/modellbau/kkmulticopterflashtool) on my PC to load each ESC with its own unique hex address. I had no problem changing the hex address of each ESC from 0x29 to a unique, new hex address. You can also read about my BlueESC programming efforts [here](http://www.homebuiltrovs.com/rovforum/viewtopic.php?f=18&t=1707&start=70). Hope this helps. Regards, TCIII AVD ---
**Author:** ![rjehangir](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/rjehangir/32/671_2.png) [@rjehangir](https://discuss.bluerobotics.com/u/rjehangir)\ **Post date:** [December 16, 2015, 3:04am UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150/3 "2015-12-16T03:04:41Z")
Ryan, The default states are fairly simple. The blue LED turns off when the thruster is initialized and the throttle is zero. When the motor is turning, the blue LED is lit. The red LED flashes for changes in state between stopped, started, etc. and also flashes out error codes if there is something wrong. The error codes are the standard of the tgy firmware and can be seen on the tgy documentation here: [GitHub - sim-/tgy: tgy -- Open Source Firmware for ATmega-based Brushless ESCs](https://github.com/sim-/tgy#troubleshooting) The behavior of the LEDs can be changed, but you’ll have to delve into the code for the ESC! -Rusty ---
**Author:** ![michael](https://avatars.discourse-cdn.com/v4/letter/m/4bbf92/32.png) [@michael](https://discuss.bluerobotics.com/u/michael)\ **Post date:** [January 31, 2016, 4:37pm UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150/4 "2016-01-31T16:37:56Z")
Rusty, Great summary! Would it be possible to add this to the documentation for the Blue ESC on: > **[BlueESC Documentation](https://docs.bluerobotics.com/bluesc/)** > > The BlueRobotics documentation site has instructions, tutorials, and guides for using BlueRobotics' products. You can contribute through Github! … under “LED Indication Lights”? Thanks! ---
**Author:** ![rjehangir](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.bluerobotics.com/rjehangir/32/671_2.png) [@rjehangir](https://discuss.bluerobotics.com/u/rjehangir)\ **Post date:** [February 1, 2016, 4:23am UTC](https://discuss.bluerobotics.com/t/blue-esc-led-behavior/150/5 "2016-02-01T04:23:50Z")
Michael, Good idea! The “troubleshooting” section in the tgy page that talks about the lights is pretty long, so I just added a link to that. I hope that helps you and others! Best, Rusty