Please switch over to using this updated version:

https://github.com/peli-pro/coldcard_address_generator
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Generate BIP84 addresses for coldcard

This litte script will take your coldcard zpub-key and generate a list of receive and change addresses that you can store somewhere for indipendent verification of the addresses wasabi wallet or electrum creates for you (only native segwit / BIP84).
This script is only a litte wrapper around a BIP84 library that can be found here: https://github.com/Anderson-Juhasc/bip84

BEFORE YOU TRUST THIS SCRIPT PLEASE DOUBLE CHECK THAT IT WORKS CORRECTLY, SEE THE LAST SECTION !!!!!

Get your public.txt from your coldcard

Insert a SD-Card in your Cold-Card

Settings -> Blockchain -> Choose Bitcoin or Testnet: Bitcoin

then

Advanced -> MicroSD Card ->Dump summary

this will create the file public.txt on your sd card. Open public.txt and get your zpub from the last section with the header:
## For BIP84 (Native Segwit P2PKH): m/84'/0'/{account}'/{change}/{idx}
you need the zpub from the second line (this line ends with ##SLIP-132##)
(##SLIP-132## ist not part of the zpub, do not copy it)

Installation

You will need to install node.js and git on your system

Ubuntu (tested for 18.04)

sudo apt install nodejs npm git  
git clone https://github.com/Anderson-Juhasc/bip84.git
npm install bip84 --save

if the last command fails you might have to do: sudo npm install bip84 --save

Windows

Install node.js from: https://nodejs.org/en/
Install git from: https://git-scm.com/
Open an elevated command prompt with admin rights:

git clone https://github.com/Anderson-Juhasc/bip84.git  
npm install bip84 --save  

Clone this repository

git clone https://github.com/peli-pro/coldcard_bip84_address_generator.git

then copy generate_bip84_addresses.js from the coldcard_bip84_address_generatorfolder into the bip84 folder.

Run

Run the following command in the the bip84 folder (replace <replace this with your zpub> with your zpub from the last step)

node generate_bip84_addresses.js <replace this with your zpub>

Example:

node generate_bip84_addresses.js zpub6rRmr7DviwWPPQFZYgpL7cniK2PCiMSMnMDaKTe37nBFHhKuD9uWeUZbrsoib7PChrvmNiw5uoAyamAFmioZx3uo2BVTKHi6YCRJUhZGHAz  

This will generate the first 50 receive and change addresses.

Testnet

Switch your Coldcard to testnet and export the public.txt.
For testnet the required key starts with vpub. Use this key as your zpub. Testnet addresses should be corret for electrum. It seems Wasabi wallet uses a different path for generating testnet addresses, so it might bei that they don't match

Verify that the addresses generated here are correct

Please verify yourself that this script generates correct addresses.

1. Compare the generated addresses with

• the addresses in your public.txt
• the addresses generated by Wasabi Wallet or Electrum

2. Use https://iancoleman.io/bip39/ and generate a NEW mnemonic (DO NOT expose your own mnemonic!).

• make the following settings:
• Coin: Bitcoin or Bitcoin Testnet
• Derivation Path: choose BIP84
• External/Internal: 0 (0 generates receive addresses and 1 generates change addresses)
  This will generate a bunch of addresses
• Use Account Extended Public Key as the zpub value and run this script
• Compare the addresses
• Change External/Internal to 1 for change addresses
• Compare with the change addresses

Why can't you use Ian Colemans BIP39 tool directly?
Because it will only generate the addresses from the mnemonic/private seed or the zprv key (which is pretty dangerous and you could loose your funds). Please don't do it. You bought a coldcard to not expose your private seed to anybody!