How to set up cod.m CC2538 + CC2592 Raspberry Pi Module for Home Assistant

It should also work for the CC2652P2 Raspberry Pi Module for Home Assistant

Biggest hurdle: Accessing Raspberry UART when running Hassio

I wrote this as a comprehensive guide to install the cod.m CC2538 + CC2592 Raspberry Pi Funcmodul v0.3. It required some info that I was able to gather from the internet in several places. It was written in Januari 2021. Things might have changed since then. I am using windows to set this all up.

Preparation

To make this work I needed these items

1. Raspberry Pi with MicroSD card with Home Assistant installed.
2. cod.m CC2538 + CC2592 Raspberry Pi Module v 0.3
3. USB-stick (altervatively a Micro-SD to SD card converter)
4. An antenna that has a u.FL connector.
   • I myself had an antenna lying around that was SMA male. So I bought a u.FL-female to SMA-female antenna conver.
   • Exxample: Bits and Parts. I had it in my mail the day after it was processed.

Alternative method

First off, this is the fastest, easiest method. I did not try this method, but instead of getting SSH access to your system this is also a possibility I was told:

1. Shut down your Raspberry Pi.
2. Take out the SSD card and place it in your pc.
3. Navigate to the correct folder (presumably mnt/boot/config.txt).
4. Edit the file as described in [Editing the config.txt file](## Editing the config.txt file). You won't have to use VI.
5. Place the Sd card back into the Raspberry Pi.
6. Follow the guide from there.

Getting an SSH Key

1. Install Putty
   • go to https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html
   • download the .msi and run it.
2. PuTTYgen should be in yout start menu (Windows key + type 'PuTTYgen' to find it). Run it.
3. Changing setings is optional; I left it to default. Press the 'Generate' button and move your mouse over the blank area to generate some randomness.
4. If you want to add some security to to using the key you can add a password here. I did.
   • Save it somewhere safe by pressing 'Save private key'. Name it whatever you want.
   • Now you have a file you can always open again by PuTTYgen and the public key will be visible again.
5. The public key we want will not be correctly saved by the 'Save public key' button. You accomplish this by doing the following:
   • Copy the public key from the text field. Be sure to copy all of it.
   • Paste it in an advanced text editot like Notepad++ or Visial Studio Code. They can be found on the internet and are free.
   • The default encoding is normally UTF-8. Set this to ANSI. (In notepad++ you select Encoding -> Convert To ANSI)
   • The default line endings are Windows (CR LF). Set this to Unix (LF) (In notepad++ you right click in the bottom right where it states: CRLF and select LF.
   • Save it somewhere and name it authorized_keys.

Setting the SSH Key

There are 2 ways to get the key onto the Rapberry Pi.

Usb Stick

1. Prepare a USB stick:
   • Copy the File we just created to a USB drive that is formatted FAT, ext4 or NTFS.
   • Give it the name : CONFIG
   • Copy the authorized_keys in the root.
   • Plug in into your Raspberry Pi.
2. Now either:
   • Import it: Go to your HA interface and click 'Supervisor' -> 'System'. Under 'Host' select 'Import from USB'. It might be hidden under the tripple dots.
   • Reboot Home Assistant

Alternate method

• Shut down Home Assistant
• Get the Micro-SD card an put it in your pc.
• Create a folder named CONFIG
• Copy the file in there
• Put the card back
• Start up your system

Connecting with PuTTY

1. Start up Putty
2. Enter the up or hostname into the field.
3. Use port 22222
4. Optionally give it a name and hit 'Save'.
5. In the left menu under 'Connection', select 'SSH' -> 'Auth'.
6. In the Authentication Parameters click 'Browse...'
7. Select yout private key (ppk file)
8. Click 'Open'
9. Log in as root, and use the password you set.

Editing the config.txt file

After you have logged in...

1. Type login
2. Make a backup; Type cp /mnt/boot/config.txt /mnt.boot.config.bak
3. vi is the only editor. Type vi mnt/boot/config.txt
   • If you have no idea how vi works (I did not); use the link below as a reference
4. Enable the line enable_uart=1 by removing the #
5. Under [all] add the line dtoverlay=disable-bt to disable it.
   • Even though I have a Pi4, this worked for me.
6. You also need to disable hciuart. However it was not set up. You can check this by running systemctl status hciuart
   • If it iss found disable it systemctl disable hciuart

Adding the module to Home Assistant

Hardware

1. Turn off the Raspberry pi.
2. Press the u.FL antenna onto the module. Make sure you place it on the u.FL straight and apply slight pressure. It will click on there.
3. Connect the module in the correct way (which is on the Raspberry Pi on the other side than the USB connectors are; hovering over the rapberry pi; not the other way).
4. The Raspberri Pi and the module will not fit in any Raspberri Case. If you want to fit it make sure you get one with a bit of spave on the top. I strapped the antenna to the case with a tie-wrap so that if you or your pet accidentally trips over the cable you don't destroy your hardware.
5. Power up.

Software

1. Go to 'Configuration' -> 'Integrations'
2. Click '+ Add Integration' icon in the bottom right and search for ZHA (Select Zigbee Home Automation)
3. For me it configured automatically. But you can look at the link at the resources

Adding a device

1. Click on the ZHA Integration (1 device)
2. In the bottom right click '+ Add Device'

Resources:

1. Access with PuTTY:
   • I followed this guide to get access to the OS: https://developers.home-assistant.io/docs/operating-system/debugging/
   • It links to a page which describes how to create the SSH key file: https://www.digitalocean.com/docs/droplets/how-to/add-ssh-keys/create-with-putty/
2. Getting to the file; after I was logged in I used some info on this thread to get it running
   • https://community.home-assistant.io/t/how-to-access-config-txt-in-hassio/139330/24
3. Info on 'vi'
   • https://www.washington.edu/computing/unix/vi.html
4. Read more about UART configuration:
   • https://www.raspberrypi.org/documentation/configuration/uart.md
5. Adding the device to Home Assistant
   • https://www.home-assistant.io/integrations/zha

Versions:

• 0.2 (2021-01-20)
  • Added the preparation part.
  • Added antenna connection to [Hardware](## Hardware)
  • Added the Alternative version of putting the Micro SD card in the PC to edit.
• 0.1 (2021-01-17) -Initial version