bioe007
Posts: 16
Joined: Tue Apr 04, 2017 11:39 pm

CM3s that die

Fri Jan 05, 2018 10:24 pm

We are experiencing a small number of CM3 modules that seem to 'go haywire' somehow when being programmed and will exhibit progressively worsening symptoms:

1. HDMI output starts to fail
2. HDMI output ceases to function (composite seems to work)
3. HDMI can't fetch EDID information anymore (tvservice -d foo.edid reports "no data written!" or similar)
2. CM3 stops booting
3. Powering the CM3 (even in a dev kit) causes the bcm2837 to get *really* hot *really* fast

We are flashing the CM3 using dcfldd similar to this:

`dcfldd sizeprobe=if bs=4M if=sd/20171215.1.img of=/dev/sdb `

Some basics about our setup -
a. We split emmc into 4 partitions, /boot / /data1 /data2
b. Linux 4.9.something'ish
c. /boot vfat, root is ext 4
d. all file systems are normally mounted read-only, there are a few configuration steps during production where /boot and/or / may be rw for a couple file operations.

We use our own carrier board. The CM3 is dead in both that and the CM3IO boards.

I suspect that during some of the configuration steps (d - above) the /boot partition is getting messed up. My suspicion originates in observing , in some instances, that if a file change happens on /boot and then the system is rebooted without 'sync' and `mount /boot -o remount,ro` then the system will be stuck shutting down for a long time, like several minutes (Normal reboot cycle time is about 15-20 seconds).

Once one of these 'long reboot' events occurs, the CM3 is usually toast.

To that end, I have compared all files in /boot on a 'bad' CM3 with a good one and see no differences (diff -q shows nothing).

I am working on imaging the entire MMC and am trying to compare against the flashed image.

Looking for any ideas about how to analyze this further... thoughts? suggestions?

Gitch
Posts: 6
Joined: Sat Jun 17, 2017 11:38 pm

Re: CM3s that die

Sat Jan 27, 2018 6:56 am

I'd be looking at the power supply and interface on your carrier board.

Are the power lines filtered and not susceptible to spikes? Do they power the CM in the correct order? What about static protection both during installation, general handling and during cable connect / disconnect processes?

Do the CM recover after a re-flashing??

KdhruvR
Posts: 8
Joined: Tue Mar 06, 2018 7:05 am

Re: CM3s that die

Tue Mar 06, 2018 8:52 am

I seem to be getting a similar issue.
My CM3 is not dead yet, although it does not boot when connected to the breadboard and HDMI for display.
the board seems to still work on the firmware that i put on it but i am unable to re-flash it

in more detail on this, my system detects the CM3 but finishes the flashing process in a matter of a few seconds.
This process usually takes close to 10 mins for a proper CM3. and after the flash it retains the previous image not the one that was flashed the latest

I would love some help on debugging this.
using a DC jack to power on the 15th pin in case thats requires

gsh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 1282
Joined: Sat Sep 10, 2011 11:43 am

Re: CM3s that die

Tue Mar 06, 2018 1:02 pm

I assume you are using the CMIO3 board to flash the device?

Have you updated to the latest version of https://github.com/raspberrypi/usbboot
--
Gordon Hollingworth PhD
Raspberry Pi - Director of Software Engineering

KdhruvR
Posts: 8
Joined: Tue Mar 06, 2018 7:05 am

Re: CM3s that die

Wed Mar 07, 2018 12:11 pm

using the latest version
and it is working for all the other boards that i have just one module is not flashing anymore.
It was working perfectly earlier.

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RaTTuS
Posts: 9992
Joined: Tue Nov 29, 2011 11:12 am
Location: North West UK

Re: CM3s that die

Wed Mar 07, 2018 12:33 pm

bioe007 wrote:
Fri Jan 05, 2018 10:24 pm
..
3. Powering the CM3 (even in a dev kit) causes the bcm2837 to get *really* hot *really* fast
...
We use our own carrier board. The CM3 is dead in both that and the CM3IO boards.
...
you possibly have some dodgy circuity that is killing the SOC i.e. putting +5V somewhere
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gsh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 1282
Joined: Sat Sep 10, 2011 11:43 am

Re: CM3s that die

Wed Mar 07, 2018 4:10 pm

OK, you answered about using the latest version of the software, have you tried flashing it using the CMIO3 board?

If the problem persists, it would be good if you'd be able to send it to us for debugging... I'm guessing the problem is related to the MSD software running on the CM3 in some way. Does it do the same thing plugged into a Linux host (Raspberry Pi) as well as a Windows host?

Gordon
--
Gordon Hollingworth PhD
Raspberry Pi - Director of Software Engineering

KdhruvR
Posts: 8
Joined: Tue Mar 06, 2018 7:05 am

Re: CM3s that die

Thu Mar 08, 2018 9:30 am

@gsh
yes i am using the CMIO3
and tried it with both linux and windows, not working.
What Mailing address would i need to send it to?
Knowing the reason behind this , is a priority for me.

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