While the Announcement some time ago of the more powerfull Raspberry Pi 5 Single Board Computer rose some questions, that isn’t a solution for the new Homey Pro because it is build on the Compute Module (in short CM4) and there was not yet anything known about a new Compute Module
Here in this Blog Raspberry Pi YouTuber Jeff Geerling had the chance to interview Raspberry Pi CEO Eben Upton at CES. During the interview we hear Upton confirming that Raspberry Pi 5 production is ramping up, and inadvertently we also get first confirmation that the Raspberry Pi Compute Module 5 is an upcoming product.
There is a Link in the blog to a document released by Raspberry Pi: released guidance for those wishing to design products based around the future board.
The rest ia a lot of speculation… (When will the CM5 be available, Will Athom bring out a new and even faster Homey Pro based on the CM5 or would it be possible to upgrade for the modders…)
One interesting thing is hopeful for Homey Pro (Early 2023) users:
What we can confirm though is that the Compute Module 5 will share the same dual connectors as the Compute Module 4.
and for the rest,
for now Patience,
Happy reading / viewing,
Have nice dreams…
Time will tel.
CM5 uses the same form factor as CM4, featuring two 100-pin high density connectors.
Interesting is section “Appendix C: Differences between CM4 and CM5”
The Raspberry Pi Compute Module 5 (CM5) maintains the same physical form factor as the Compute Module 4 (CM4), featuring two 100-pin high-density connectors. However, several pin functions have been reassigned in the CM5, which could lead to compatibility issues when used with hardware designed for the CM4.
Notable changes include:
USB 3.0 Ports: Pins previously designated for camera (CAM0) and display (DSI0) interfaces on the CM4 are repurposed as USB 3.0 ports on the CM5. Specifically:
Pins 128 (CAM0_D0_N) and 130 (CAM0_D0_P) are now USB3-0-RX_N and USB3-0-RX_P.
Pins 134 (CAM0_D1_N) and 136 (CAM0_D1_P) serve as USB 2.0 signals USB3-0-DP and USB3-0-DM.
Pins 140 (CAM0_C_N) and 142 (CAM0_C_P) are now USB3-0-TX_N and USB3-0-TX_P.
Similar reassignments apply to DSI0 pins for the second USB 3.0 port.
Power Management:
Pin 111, previously VDAC_COMP, is now VBUS_EN, controlling USB VBUS power.
Pins 94 (AnalogIP1) and 96 (AnalogIP0) have become CC1 and CC2, respectively, for USB-C current negotiation.
Peripheral Controls:
Pin 16, formerly SYNC_IN, is now Fan_tacho for fan tachometer input.
Pin 19, previously Ethernet nLED1, is now Fan_PWM for fan control.
Pin 92, RUN_PG on the CM4, is now PWR_Button, emulating the Raspberry Pi 5's power button functionality.
So the question is, would be CM4 replaceable by CM5 ? On the first view it seems it might be dangerous road (depends on real pin usage) but yet, I guess we will not get Emile or someone from Athom team here saying Yes or No…
If IO boards are backwards compatible with “with reduced functionality” and in case Athom did follow standards defined by Raspberry… it could be working ? Any thoughts anyone ?
FWIW on what I got on responses from Athom members already now: (free translations)
haha, no that doesn’t work yet,
it is a software issue …
we have it already running long time…
support is now specific for cm4. Whether and when we will provide cm5 support is still the question.
So despite we can replace the CM4 for a CM5 we probably need to upgrade / fix Rasbian for CM5 compatibility and that after each FW upgrade… (if that works)
So FYI, in case anyone is interested and would like to share some advice. I tried running kernel 6.6 as first step, because I believe it’s probably the only way to have running CM5 on it, unless I would try compiling Kernel 6.1 with necessary modules (which I’m even not sure it’s possible).
Unfortunately 6.6 changed the way GPIO is accessed and also shifted UART device names, so as I don’t really want to change the code of Homey, I had to implement dirty workaround using sysfs-gpio-shim with some OS changes, but this workaround is probably not fully capable of taking over some of basic functionalities. So eg. since the upgrade I have been unable to reset Homey via PIN, enter ZWAVE learning/pairing etc. Other then that it was running fine for 2 weeks or so.
So this is “progress” so far, I would need first to fix those issues prior even trying to replace the module itself… if anyone is interested to share his thoughts … happy to hear some ideas.
Nope, didn’t get to it yet, considering to sell my CM5 and rather use CM4 with 8GB RAM, 32 GB storage instead. The problem is that this approach would have to be repeated each time after upgrade and also it seems that Athom is not going to switch Kernel anytime soon. If Homey would have Kernel 6.6 “from stock”, it would be much easier, which is not the case…
