Home Assistant Yellow gets CM5 support in HAOS 14

Blog
1

We launched our Home Assistant Yellow over two years ago, with the design philosophy that it would grow and extend its capabilities with its users’ needs. Need more storage, add an NVMe drive. Need Matter over Thread instead of Zigbee, change the firmware.

Thanks to Raspberry Pi providing us with an early sample, we have been able to add Compute Module 5 (CM5) compatibility to the Home Assistant Yellow, which will be included in Home Assistant OS 14 (along with some other hardware support). This gives current and future users a great option to get more performance if they need it, but we must say that CM4 is still more than enough for most Home Assistant users’ needs.

As part of the Open Home Foundation, we fight for privacy, choice, and sustainability in the smart home. The Yellow achieves all three, and this announcement only improves the choices available and long-term sustainability.

Using Compute Modules

When designing Yellow to give our users the ability to expand the capabilities of the device we chose Raspberry Pi’s Compute Module platform. It allows users to increase the RAM, add eMMC, built-in Bluetooth, or even get more speed 😉 - without having to replace the Yellow - all you need to do is get a new module. This is also great for the repairability of the product over its lifetime.

Though it was designed for the Compute Module 4 (CM4), we always hoped it would be compatible with its future successors. Over the past couple of months, we’ve been updating firmware and testing early hardware, and it is indeed compatible. Due to changes on CM5, the installation method is slightly more complex than it was on CM4, which is detailed below.

What CM5 could bring

I must admit, it is fun to play with the latest and greatest hardware (while also finding new uses for the hardware it replaces - old Pi products make great Wyoming satellites). In most use cases, such as running automations or connecting an average home’s worth of devices, the majority of users will not notice any difference between a Green, CM4, or CM5.

For certain power user needs CM5 might provide big improvements. Some Pi 5 users have seen nearly 3x improvements in ESPHome compilation times; saving a minute or two per device can really add up in big deployments. Another area where CM5 can excel over CM4 is running local speech-to-text processing if you’re using Assist fully locally.

Installing on CM5

For the Home Assistant Yellow, we have two ways to install Home Assistant OS onto the Compute Module. One is very easy and quick (using USB 2.0), while the other is more complex (using rpiboot). Unfortunately, due to firmware differences with CM5 it cannot boot off USB 2.0 devices (though the USB 2.0 ports work once the device is booted).

If you already have a Yellow running Home Assistant OS, upgrading to CM5 can be a drop-in replacement, but in some circumstances it can be more complex,

  • CM4 Lite (no eMMC) with NVMe storage - Update to the latest HAOS (version 14.0 or greater - as of writing 14.0 is still pre-release, but will be stable when CM5s start to reach consumers), power it down, swap the CM4 Lite for a CM5 Lite, and you’re good to go.

  • CM4 with eMMC (regardless if you are using NVMe or not) -  Download a backup of your Home Assistant, power down your system, and install Home Assistant OS on the CM5 using rpiboot (the more complex installation method). Once installed restore the backup.

  • New Yellow with CM5: You will need to install Home Assistant with rpiboot (the more complex installation method).

For full details on how to set up your Home Assistant Yellow visit our documentation.

CM4 is still great

If you have, or were looking at getting, a Home Assistant Green or Yellow with a CM4, both are more than capable. A third of all Home Assistant users are using Pi 4 class hardware.

In fact, according to our opt-in analytics, more people are using Pi 3 hardware than Pi 5 hardware (granted the Pi 5 has only had official support since February this year). Home Assistant continues to get updates that improve its speed on all hardware, most recently faster backups and reboots. This allows people to keep hardware running longer, and in the end that is our goal 🌎.

CM4 is not only powerful enough for most users, it also has a long life ahead of it. Raspberry Pi has even confirmed that they will fully support CM4 until 2034💪, and will continue to manufacture them.

Other additions to HAOS 14

On the topic of newly supported hardware, our release of Home Assistant OS 14 will bring support not only for CM5 but also for the Hailo-8 AI accelerator. This is the AI accelerator found in the Raspberry Pi AI Kit or the even more powerful Raspberry Pi AI HAT+ released last month, which is exclusively for the Raspberry Pi 5. For those using a Pi 5 they can now offload AI processing, like object or person detection, to this efficient add-on.

Conclusion

We’re incredibly proud that, all this time later, the Home Assistant Yellow continues to be one of the best options for power users. We are excited to see how our users take advantage of CM5, and it’s great to see CM4 continue to be a great option with long-term support.

This is a companion discussion topic for the original entry at https://www.home-assistant.io/blog/2024/11/27/home-assistant-yellow-gets-cm5-support
8 Likes
2

Good news, when wanting to upgrade from an existing yellow setup, do one need new thermal pads and/or a new cooling solution for the yellow?

2 Likes
3

The existing heat sink fits onto the Compute Module 5, even the blue thermal pads work but need repositioning. The thermal pad for the main chip is slightly too small (the BCM2712 is larger), but it seems not to matter much in practice. So in general, the existing solution works quite well.

That said, the Compute Module 5 under full load produces a lot of heat. So over time, if your system is continuously under high CPU load, the CM5 will throttle down.

1 Like
4

Is there a compatible dual M.2 PCIe switch adapter that you can buy for the Home Assistant Yellow (and other CM4/CM5 carrier boards with only a single M.2 slot) that would allow us to use both a Hailo-8 AI M.2 module and a NVMe SSD harddrive in it at the same time?

The point is that it would be awesome for Home Asssistant Yellow users could use a M.2 AI accelerator card it without sacrificing the NVMe SSD storage M.2 slot, thus the need for some kind of PCIe switch adapter in a nice slim format.

There are at least some dual M.2 HAT(s)/Shield(s) with PCIe switch chip for the regular Raspberry Pi 5 that allow you to use a Hailo-8 AI accelerator (Raspberry Pi AI Kit) and a M.2 NVMe SSD at the same time? See example Geekworm X1005 PCIe to M.2 NVMe SSD PIP Bottom for Raspberry Pi 5 which by reports looks to also support Hailo-8 AI Accelerator but that adapter does not have an M.2 input interface:

Maybe it would be better to ask Jeff Geerling such questions as he tested a Raspberry Pi 5 with six (6!) AI accelerator cards using an akward PCIe adapter and a M.2 PCIe switch expansion board on the Pi 5? :wink:

https://www.jeffgeerling.com/blog/2024/55-tops-raspberry-pi-ai-pc-4-tpus-2-npus

6

Since upgrade from CM4 lite is easier, would it be possible to upgrade from CM4 with emmc to CM5 lite?

If i buy CM5 lite and, install using rpiboot, can just restore backup from previous CM4 with emmc installation?

BTW some Polish, and probably other, reseller have preorder for 16GB ram version. Do you think that there will be 16GB in the first batch as official page only mentions 8G ram.

Also if you already have CM5 devkit and are willing to try CM4 in it - can you please try? I think devkit might be a nice way to have use for the old CM4 after upgrading.

7

Can the Home Assistant Yellow be revised?

8

Thanks for the info.
Thats good to know.
CPU load has not yet been a huge issue, so I’ll ponder a bit next month whether to upgrade or not…

9

Is there gonna be an updated version of the YELLOW hardware for CM5? Although it seems not so necessary

1 Like
10

Why?

1 Like
11

While a refined revision with minor changes might be a good idea if could simply make that updated revision boot from USB so can make installations to CM5 less complicated (to enable USB boot for easy installation so do not have to mess with rpiboot).

But I instead would rather see a brand new larger high-end Home Assistant OS appliance box in this series with more major changes such as more M.2 PCIe slots, preferably at least three M2-slots, to allow for both adding two NVMe SSD harddrives in a RAID-1 (disk-mirroring for redundancy) in combination with an AI accelerator like the the Hailo-8 AI accelerator (Raspberry Pi AI Kit), as well as four or more USB 2.0 ports for optional additional USB radio dongles (Zigbee, Thread, Z-Wave, Bluetooth, and others) with external antennas. Perhaps also an SD-card slot for local backups.

Wish list for a more expensive Home Assistant appliance variant of the Home Assistant Green/Yellow:

  • Two long M.2 slots for two NVMe SSD disks.
  • One or two short M.2 slots for AI accelerators.
  • Four or more USB 2.0 ports for external USB dongles.
  • SD-card slot for optional local backups.

Such a device could be based on the CM5 or they could simply do what they did with the Home Assistant Green and just go with a fast Rockchip SoC as long as it is fully supported by the latest Linux kernel.

AI accelerators is going to be needed for local AI via Assist and the upcoming Home Assistant Voice Satellite hardware, so need at least another M.2 slot for a AI AI accelerator card if also want an NVMe harddrive in the same box, otherwise you are going to need a separate box for local AI acceleration if you do not want to use the cloud.

1 Like
12

According to Jeff geerling - the cm4 needs cooling… a new HA Yellow specifically for MC5 might be worthvile.

1 Like
13

The “restore from backup” option is always possible and rather easy. Going from Lite to Lite doesn’t even need a restore, so that is the advantage.

That said, going from CM4 with eMMC + NVMe data disk to CM5 with eMMC + NVMe data disk will become easier too: On first boot the new installation on the CM5 will automatically detect the NVMe data disk, and use it from the getgo. A backup is still worthwhile though!

3 Likes
14

I think more devices, more things to care about, less reliability.

I do run yellow from first month it was distributed and only issue I have was caused by ethernet cable becoming lose by itself. This is quite a rare experience these days and I would not want to lose it for new features.

Even only reason to upgrade performance is that i do have quite a lot of esphome devices that i do compile on the HA server, because i’m lazy :slight_smile: .

15

I have the yellow and CM4 with eMMC + NVMe data disk. I installed the OS on the NVMe.

  • When I upgrade to CM5 with eMMC + NVMe data disk, do I still need to do a clean install and then restore the backup or does it work out of the box without doing a clean install?

  • Is the version with 16GB ram also compatible with the yellow?

16

I would generally agree with the rest of your post except the above. With so many way of scheduling backups off local storage, why would RAID-1 be of any benefit?

It’s an added fixed cost of production as well as for the end consumer who now has to buy 2 drives instead of one, just to save a few minutes in the unlikely event their SSD goes bad.

Ironically, adding an extra cost would almost guarantee that people would go for cheaper (less reliable) SSDs, therefore increasing the risk of actually having a drive fail on them.

17

Looking forward to a CM5 based HA Yellow .

18

For reference, even the RK3588 SoC which is the current flagship of Rockchip can not can today not compete with a dedicated AI accelerator M.2 card like the Hailo AI processor series (where the high-end Hailo-8 model features up to 26 tera-operations per second (TOPS) in performance, so having multiple M.2 PCIe slots would be most important on high-end model.

Ensuring higher uptime is the main reason.

Backups is not enough if the main goal is to aim for 24/7-365 as then you want redundancy for parts that are more common to fail, so achieving higher than basic uptime by having automatic fail-over when the harddrive goes bad is usually step-2 (I believe anyone who rely on Home Assistent storage fail can attest to that).

This is the same reason why you preferably as step-1 want a small UPS-battery for Home Assistant and your LAN (router/firewall and network-switches).

Otherwise I think that if recording video from (security) cameras directly to you Home Assistant is an use case example, and you your backups only runs once every night or less then you might loose video of somerhing important that happen since the last backup if the harddrive fail.

19

Maybe we could do an s/m/l strategy and have a red model with redundancy and high availability in mind together with lets say a radio transmitter/sdr instead of just an rtl 433 and zigbee receiver and ai accelerator and some other fancy stuff?

20

I like the idea of having low-end, value-end, and high-end models on the main appliance, but regardless of the variant it is just add many USB 2.0 ports and keep IoT radios as dedicated USB adapters with separate dongles for each radio type, that way they do not add cost to the main appliance for those that do not want them and users can pick and choose, plus it makes it easier to upgrade or replace a specific radio dongle.

21

Having low end, mid range, high end becomes a development cost vs commercial sales thing. Nabu Casa is a business and ultimately they need to make money off hardware as the software is free. There may be a niche market for a high end system, with all the bells and whistles, but would it be commercially viable? Likely not when it is competing with the likes of Smartthings, Homey etc.
Most home users would be more than happy with a green, and maybe a Thread or Zigbee dongle to add the extra radio. A significant amount of users would not want more than the current Yellow offers with a CM4 installed. Most wouldn’t even need the power of a CM5. As far as up time, well all electronics can fail, but eMMC or NVMe storage are probably not really on the high failure list for majority of installs that are not really doing a lot of writing to the database, and not being used for media or CCTV or stuff like that.
A lot of the more advanced features in Home Assistant, and the advanced use cases, are only used by a small number of users, and they are usually the ones most active on the forums, so you hear these niche use cases maybe a lot more than the actual real world use case would be.

I love the idea of a niche high end system too, but this might be more something for the people who would use these systems to build at home for themselves. That’s the joy of having the software opensource and compatible with many platforms. You can pretty well build anything you can dream of. It just is unlikely to be commercially viable for a company needing to make money to pay for the development of a niche system

1 Like