User avatar
DavidS
Posts: 4334
Joined: Thu Dec 15, 2011 6:39 am
Location: USA
Contact: Website

Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 7:16 am

Using my primary Raspbian install that I have been using on my RPi 3B I decided to boot my RPi 2B. To my surprise it failed, stuck at the 4 color pre-boot screen. So I updated the firmware, just incase it was a corrected bug, same result, tried my backup Raspbian SD used with the RPi 3B same results on the RPi 2B.

So I booted the RPi 3B and both Raspbian installs still work perfectly. The ONLY hardware difference between the attempts was the RPi (3B or 2B), using the same exact USB periphials, monitor, etc, no differences.

Also note that the RPi 2B works perfectly if I boot into Puppy Linux, RISC OS, or even a fresh flash of Raspbian (once I configure it to work with my monitor anyway).

Knowing that the Raspbian had no trouble on the 2B before I had a 3B (and the same install, though updated since), I can not explain this.

Do to this puzzle; I must ask:
What could possibly be causing this? Is there something in the updates that is specific to which ARM CPU it is installed on (kernel module that loads before Linux takes the display or something)? Or is there something that gets updated in the firmware when run that is model specific now?

I have no idea.

Thank you in advance for any input
RPi = The best ARM based RISC OS computer around
More than 95% of posts made from RISC OS on RPi 1B/1B+ computers. Most of the rest from RISC OS on RPi 2B/3B/3B+ computers

User avatar
DavidS
Posts: 4334
Joined: Thu Dec 15, 2011 6:39 am
Location: USA
Contact: Website

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 2:54 pm

Ok I am guessing that no-one else knows either?
RPi = The best ARM based RISC OS computer around
More than 95% of posts made from RISC OS on RPi 1B/1B+ computers. Most of the rest from RISC OS on RPi 2B/3B/3B+ computers

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27394
Joined: Sat Jul 30, 2011 7:41 pm

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 4:00 pm

It does sounds very odd, Raspbian is built for the least common denominator - the Pi1/Zero - and a SD card should work on all Pi models.

Any kernel boot output at all?
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

User avatar
Jednorozec
Posts: 809
Joined: Sun Nov 24, 2013 2:17 pm
Location: Deposit, NY

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 4:26 pm

Compare the contents of /boot on a Raspbian image that works and one that fails.
The most important leg of a three legged stool is the one that's missing.
It's called thinking. Why don't you try it sometime?

User avatar
Paeryn
Posts: 3074
Joined: Wed Nov 23, 2011 1:10 am
Location: Sheffield, England

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 4:45 pm

Did you add/modify any options in config.txt that work for the RPi3 but not RPi2? (Thinking here of things like changing the clock frequencies.)

Chances are there is something you've done to your installation that the RPi2 doesn't like. As JamesH said, Raspbian in it's default state is designed to work on all RPis and I'm sure there would have been a lot of complaints if at any point it didn't.

Just to check, I swapped my sdcard from my RPi3 into an RPi2 and it worked fine, that's a version that started out life on the RPi2 and has been updated regularly on the RPi3.
She who travels light — forgot something.
Please note that my name doesn't start with the @ character so can people please stop writing it as if it does!

User avatar
DavidS
Posts: 4334
Joined: Thu Dec 15, 2011 6:39 am
Location: USA
Contact: Website

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 5:02 pm

jamesh wrote:It does sounds very odd, Raspbian is built for the least common denominator - the Pi1/Zero - and a SD card should work on all Pi models.

Any kernel boot output at all?
My thinking would be that it should work. I am at a loss as to why it boots with out issue on the RPi 2B and not on the RPi 3B.
RPi = The best ARM based RISC OS computer around
More than 95% of posts made from RISC OS on RPi 1B/1B+ computers. Most of the rest from RISC OS on RPi 2B/3B/3B+ computers

User avatar
DavidS
Posts: 4334
Joined: Thu Dec 15, 2011 6:39 am
Location: USA
Contact: Website

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 5:07 pm

Paeryn wrote:Did you add/modify any options in config.txt that work for the RPi3 but not RPi2? (Thinking here of things like changing the clock frequencies.)

Chances are there is something you've done to your installation that the RPi2 doesn't like. As JamesH said, Raspbian in it's default state is designed to work on all RPis and I'm sure there would have been a lot of complaints if at any point it didn't.

Just to check, I swapped my sdcard from my RPi3 into an RPi2 and it worked fine, that's a version that started out life on the RPi2 and has been updated regularly on the RPi3.
The only options that I change in config.txt for the Raspbian are related to being able to use my monitor, and those are the same on the RPi B, RPi 2B, RPi 3B, they are:

Code: Select all

hdmi_drive=2
hdmi_group=2
hdmi_mode=68
and that is what is being used, the rest of the config.txt is original, as provided with the firmware. There are times I use hdmi_mode=23 instead of hdmi_mode=68 though not in this testing.
RPi = The best ARM based RISC OS computer around
More than 95% of posts made from RISC OS on RPi 1B/1B+ computers. Most of the rest from RISC OS on RPi 2B/3B/3B+ computers

mutley
Posts: 61
Joined: Sat Jan 02, 2016 8:06 pm

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 9:55 pm

A clean install should work on either PI, but once you've done the raspberry update that updates the firmware, the SD card seems to be locked to that particular model. I've had similar experience between Zero, B and 2+, it seems to be something to do with the files in the overlays directory under boot. Can't say I really look at it hard though, as I simply flashed another CD card, so I may not be 100% accurate.

dan3008
Posts: 1172
Joined: Wed Aug 15, 2012 1:05 pm

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 10:11 pm

mutley wrote:A clean install should work on either PI, but once you've done the raspberry update that updates the firmware, the SD card seems to be locked to that particular model. I've had similar experience between Zero, B and 2+, it seems to be something to do with the files in the overlays directory under boot. Can't say I really look at it hard though, as I simply flashed another CD card, so I may not be 100% accurate.
Sounds a bit like when you try and boot a hard disk from one computer in another. When running os updates ect (and installing software) some hardware specific things get done (such as memory addresses). So if for example, I stuck my laptop hard disk in my desktop, it wouldnt boot, because the hardware is wrong. Sounds like the Pi might do something similar?
dan3008 wrote:Pays your money, takes your choice

User avatar
Paeryn
Posts: 3074
Joined: Wed Nov 23, 2011 1:10 am
Location: Sheffield, England

Re: Failure Switching RPi3B -> RPI2B

Thu Sep 22, 2016 11:09 pm

mutley wrote:A clean install should work on either PI, but once you've done the raspberry update that updates the firmware, the SD card seems to be locked to that particular model. I've had similar experience between Zero, B and 2+, it seems to be something to do with the files in the overlays directory under boot. Can't say I really look at it hard though, as I simply flashed another CD card, so I may not be 100% accurate.
It shouldn't matter what model the card was updated on, unless you've installed something that runs at boot time which doesn't work on older RPis, and all the software on the official repo should be 100% compatible between all versions. The only times a version might not work is when it's a version that is older than the model you are trying to run it on.

I just tried my RPi3 sdcard on my old RPi1 (an old 256MB one at that), it works fine just like it does on my RPi2 (apart from taking ages booting, especially to the desktop). It's definitely been updated many times on the RPi3 and this is the first time it's been put in my RPi1.
She who travels light — forgot something.
Please note that my name doesn't start with the @ character so can people please stop writing it as if it does!

User avatar
DavidS
Posts: 4334
Joined: Thu Dec 15, 2011 6:39 am
Location: USA
Contact: Website

Re: Failure Switching RPi3B -> RPI2B

Fri Sep 23, 2016 4:53 am

After another update everything works fine on both RPi's. I do not know what was wrong with it, though whatever it was got corrected with an even newer update to the firmware and kernel.
RPi = The best ARM based RISC OS computer around
More than 95% of posts made from RISC OS on RPi 1B/1B+ computers. Most of the rest from RISC OS on RPi 2B/3B/3B+ computers

Return to “General discussion”