Do you think the power is enough for the cm5? I have CM5 4/32 with wifi. I’ve noticed that if my batteries are below 50% - then I would experience crashes more frequently (e.g. while watching Youtube in 1080p). Also I have RTL-SDR v4 connected to the internal usb pads of the expansion board. If the batteries are fully charged - it works stable for long periods of time. If batteries are closer to 50% and/or I turn on the screen backlight to max - it would randomly disconnect.
Ya I don’t think the CM5 like it when the voltage gets low. I’ll have to test and see when it happens. If it happens at the same voltage…
I want to try and stuff 2 10,000mAh LiPo cells inside, I found 2 that should fit. Then write a script to warn me then shutdown 5 mins later, before then panel cuts out.
The CM4 also cuts out under full load when it is overclocked, and the batteries get low. Same with the CM5.
Just as an update, the screen still needs a few tries to work most times, on a cold boot with the latest versions.
But interestingly it then sometimes turns on when a shutdown is triggered, and actually shows the shutdown messages. So it must really be a thing that can be resolved with some differences in timing.
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My opinion is that the voltage regulator on the carrier board is the issue. RasPi were very clear about using high power supplies with the “normal” Pi4 and Pi5, I’m betting the uconsole is just barely making it with a normal clock CM4.
That said, I have not logged the voltage on mine to see what is happening, I’ll have to do some digging and see what my scope needs to record stuff like this. Little dips can flip a bit or two.
The ‘voltage_min’ of the battery is 3.3v, which is set too conservatively.
So I set it to 2.9v, which is greater than the lowest safe cut-off voltage of Samsung battery 2.65v.
Did some more testing. CM5 4/32 wifi. With batteries around 70% and low backlight - I would get 4.82v on USB that goes out of the expansion board under 0.22A load. With high backlight - that voltage drops to 4.78 - 4.76. With full batteries and full backlight - it is 4.82 - 4.83. Another thing I noticed - I initially covered only the main chip with a thermal pad. And when I was measuring voltages I took a peak with my thermal camera on the board. The RP1 chip was rather hot - getting up to 70C. After covering it with a thermal pad (slightly thicker than the main) - I did a stress test of sorts and didn’t have a single crash compared to having at least 5 random ones in the same amount of time without the extra thermal pad. The “stress test” is connecting the charger, launching SDR++, tuning to an FM station, let it sit in background, sound on, opening YouTube and playing some long video 1080p for hours.
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I bought the cheap ones on aliexpress (“cheap” its a ducking extruded pieace of aluminium ) and it came with a thermal pad and to be honnest there is no way its going anywhere 
just wipe the surface clean witn alcool and slap it right in the middle of the hanger witch by total luck it was exactly the right size and that’s it , works AOk with cm5 capped out it never thermal trottled and max temp was 44c ! Al try to find you the aliexpress reff if you want
Mind you the one rex indicaded probably makes more sence mine is obviously over kill but … i think it looks cool haha
OK, screen issue is definitely solvable. (not by me, i’m just a user, but one of you smart guys can figure it out)
I was on my 6th of 7th SD card to try and still having same issue. Found via an external monitor that it is booting, just no screen. Tried multiple times, on just battery, plugged in, battery pulled and re-inserted, etc etc… No go.
This morning, just grins, I turned it on again after it had been sitting all night, and it popped right up. Working perfectly at the moment. Bit afraid to turn it off though.
So guessing something in the start up sequence can be tweeked to get around this problem?
CM5 feels so much snappier vs CM4.
Using 4GB CM5 lite with a 128G TeamGroup PRO+ SD card.
Guess I messed up the install at some point. It is a 128G card but I’m only seeing 4.8G allotted to / and it is 100% full. I wrote the latest image to card using Raspberry PI Imager. For any having same problem, I was able to expand it using gparted.
I also had issue with keyboard after install. Had to run sudo raspi-config, Localisation Options, Keyboard to reset it again. I picked US keyboard during install but afterwards, I was for example getting a * instead of a @ when hitting shift 2.
Great work! My CM5 lite should be here Friday but I’m glad you figured it out already. Now just the panel and lower battery issues.
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Hi
This doesn’t work for me.
So i have a CM5 lite
Black screen on boot with batteries. Always, tried it a dozen times.
Also have to remove them everytime to try again.
With external power (and no batteries installed) it boots 1/4.
Looks like when i have booted, the chance increases to 5/1.
After changing the eeprom, i don’t feel any change.
Thx for the research !
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oops there was typo on script. try again! sorry!
I edited installation script above.
Hi! I’m trying with all my SDs, and the “endurance” (1) type appear much more difficult to boot. There is a chance it’s due to the “negociate SDR mode”, I think. (I’m a software noob^^) Tests continues…
(1) Endurance : Sandisk high endurance 128
EDIT : “Endurance” work ! I’ve reinstalled all the Rex’s stuff and the Paragonnov’s tweaked eprom before retry. (and mega thanks to you, guys!!)
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Now I test stability and plug-unplug (power, HDMI…) combinations to verify ^^
CM5 is sooooo fast !
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Tried a few power cycles now with these changes and so far, it has come back every time.
Only thing I’ve notice off so far is that the battery level is no longer getting reported. Just says 0%.
@romeyde @paragonnov with the 6.12.y kernel is the panel booting every time correctly?
6.12 has a different way of checking the battery then 6.6, i’ve noticed this when testing 6.8 and 6.10 the applet should be updated when rpi moves to 6.12.y
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I’ve power cycled several times now and it has come back every time.
“the applet should be updated”
Something I can do?
no, you can switch DEs rpi should be switching soon to 6.12.
Chiming in to say I updated to the 6.12.16 kernel on CM5 Lite from paragonnov’s post, did the installation steps.
My system always boots, when USB power is connected the screen turns on, without USB power screen never comes on.
Also when USB powered and left inactive, the screen turns off automatically, but never comes back on when I mess with the keyboard or ball.
I know the system is booting because IP comes up in ping and I can ssh in.
Looking forward to getting this working, when booted with screen on the CM5 is so noticeably faster. Like I could open firefox and watch a YT video while working on SDR stuff at the same time.
Edit: after 6 tries it booted with screen on battery power only
Did you do the SD card fix too?