Table of Contents

Replacing and Reimaging the Nebra Indoor and Outdoor EMMC Key / SD Card

Required Tools:

Required software:

Inside the Nebra Helium Miners:

Contents of the Nebra Indoor Miner:

Nebra Indoor Miner

Contents of the Nebra Outdoor Miner:

Nebra Outdoor Miner

  • 1.) 9-16V @ 15W DC 6.5MMx2.0MM Barrel Jack
  • 2.) Ethernet Connector
  • 3.) LED Indicator
  • 4.) Interface Button
  • 5.) 4G / LTE Module Connector
  • 6.) Sim Card Slot

How to replace the SD Card

Step 1: Acquire the config.json file from the EMMC Key:

  • Download and install Raspberry Pi USB Boot, you’ll need this to boot the compute module as a usb file system
  • Identify the and adjust jumper pins on the CM3 daughterboard for programming mode
  • Daughterboard Overview
    • 5.) Micro USB Port used for Imaging
    • 7.) JP4 USB Jumper - Used to switch between normal operation and flash mode, ensure it is in position 1-2 for normal operation and 2-3 for programming.
    • 8.) JP3 Power Jumper - Allows the module to be powered from the Micro USB connector. Only connect when programming from PC and ensure mainboard is not connected.
  • Move the JP4 Jumper to position 2+3
  • Plug in a usb cable and run the Raspberry Pi USB Boot utility
  • Open your file explorer and you’ll see a drive called “resin-boot”. Retrieve the “config.json” file from the directory
  • Unplug the usb cable and reset the JP4 jumper to position 1+2

Step 2: Flash new sd card with the Balena Raspberry Pi CM3 Image:

Step 3: Copy the original config file to the new sd card:

  • Unplug your micro sd card reader and plug it back in after finishing step 2
  • You’ll now see a drive in explorer called “resin-boot”.
  • Copy the config.json file you copied earlier and overwrite the config.json file that is already on the sd card.

Step 4: Install the new sd card and reassemble the Nebra Miner:

  • Install the SD card in the slot in which the EMMC key was previously.
  • Reassemble the miner
  • When first powering the newly flashed Nebra Miner, plug it in with ethernet for 20-30 minutes before setting up wifi connections again.

Step 5: Profit?