Emax Nano 20A ESCs

Problems Updating EMAX Nano ESCs

When I ordered all the bits for my first Quadcopter build I didn’t do much due-diligence.  That’s how I ended up spending tens of hours trying to update the BLHeli firmware on the EMAX Nano ESCs.  This post takes you on my journey of frustration and enlightenment.

You can buy Emax setups from Hobbyking complete with motors and propellors at really good prices like I did.

Build a quadcopter
Emax MT2204 Bundle

Like all my other cheap parts I knew I should immediately try to flash on the newest firmware.   Instead left it until I had mounted the Emax Nano onto my frame.  That was a mistake.

Why Update Your Emax Nano ESCs?

When you buy things “cheap” or long after their release theres a very good chance that you’ll be several versions of Firmware behind.  While the older Firmware may work fine the moment you have any inkling of an issue the first advice will be “Update”.  Better to get that out of the way BEFORE you build the Emax Nano ESCs into your frame!

Using BLHeliSuite will also let you setup the ESCs to ensure they are configured correctly for your Quadcopter.  You can get the BLHelisuite Software here:  https://blhelisuite.wordpress.com

The Missing Steps

If you wait until you’ve mounted your ESCs thinking you can flash them via the Signal leads then you’re wrong.

IMG_4270Strip down to Flash before building into your Quadcopter!
Strip down to Flash before building into your Quadcopter!

Flashing EMAX Nano ESCs requires:

  1. Strip the Heatshrink and connect RED, WHITE and BLACK wires to the C2 Programming Pads.  Check out the locations in this PDF: blheli-supported-silabs-escs (Page 35/36)
  2. Use a programming adapter of your choice to connect to these leads.  For a full breakdown of the Programming hardware options:  blheli-programming-adapters
  3. Now that you’ve completed the initial setup you have a few options;
    1. Use the above method every time you wish to update or manage your ESCs
    2. Locate and remove the “voltage divider resistor” from the ESCs signal input to let you flash using 1-wire or Flight-Control methods.
    3. Use a 3.3V supply and a pull-up resistor in conjunction with either 1-wire or Flight Controller based methods.  (http://www.rcgroups.com/forums/showpost.php?p=35670107&postcount=153)
Arduino Nano Pinout
Arduino Nano Pinout showing 3.3V output which can be used to pull-up the programming voltage.

The Variations:

There are a lot of combinations of Emax Nano ESCs that have this issue:

The Emax Nano 12A v1 (http://www.rcgroups.com/forums/showpost.php?p=33523459&postcount=97)

Emax Nano v1 12A ESC
Emax Nano v1 12A ESC







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Geek, Car Guy, Former entrepreneur looking for the next big thing while doing the things I should have done 20 years ago. Key pusher and thinker for a large organisation who dreams to be doing something else.

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