Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Display testing

Tue Sep 22, 2015 11:47 am

We have three systems under test in our laboratory, all behave similarly, eliminating any hardware problems.

For the most part, once the display/touch is up and running it never seems to fail.

However, on reboot (and reboot with power) the touch occasionally (5%?) fails -- display is ok.

On rare occasions, on reboot, the display becomes incoherent (white, fuzzy) and requires a hard power cycle.

Thank you.

gsh
Raspberry Pi Engineer & Forum Moderator
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Re: Display testing

Tue Sep 22, 2015 11:58 am

Have you updated the firmware using rpi-update, a bug in the I2C communications has been fixed in the last few days

Gordon
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Gordon Hollingworth PhD
Raspberry Pi - Director of Software Engineering

Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Re: Display testing

Wed Sep 23, 2015 12:16 pm

gsh wrote:Have you updated the firmware using rpi-update, a bug in the I2C communications has been fixed in the last few days

Gordon
rpi-update is already the newest version.

gsh
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Re: Display testing

Wed Sep 23, 2015 1:04 pm

You say 5% is that across all devices (i.e. are you finding that any device fails 5% of the time, in which case I should be able to reproduce the problem here)

Gordon
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Gordon Hollingworth PhD
Raspberry Pi - Director of Software Engineering

Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Re: Display testing

Wed Sep 23, 2015 6:16 pm

gsh wrote:You say 5% is that across all devices (i.e. are you finding that any device fails 5% of the time, in which case I should be able to reproduce the problem here)

Gordon
To be accurate, we re-ran the test. Our text procedure is to repeatedly reboot. Each time, we make sure we see a cursor and then test the functionality of the touch via an app with a button. The test automatically repeats the boot every 90 seconds.

We have 3 machines (say, A, B, and C). With 3 machines booting every 90 seconds, we get two boots per minute. We ran the test for more than an hour, so we totaled about 150 boots.

During this sequence, we got 4 Display failures and 9 Touch errors, distributed as follows:
A had 2 Touch failures and 2 Display failures
B had 7 Touch failures and 0 Display failures
C had 0 Touch failures and 2 Display failures

Touch failures occur when either the cursor is absent, or it is frozen. A reboot always restores the Touch failure. On some occasions, the cursor is totally absent, but on others, it appears and is frozen. Our application comes up 10 seconds after boot and the cursor lands on its edit pad, and we see the cursor frozen as a vertical bar (text), so it seems to have frozen after some delay from the boot.

Display failures occur when the screen appears incoherent, grey, random pixels. A reboot does NOT correct the Display error, although on one occasions, it came back after a few reboots. Otherwise, Display errors require a power cycle.

In no cases were the failures due to boot failures... I puttty'd into the machine and it continued to work ok.

Hope this helps.

gsh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
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Re: Display testing

Wed Sep 23, 2015 6:32 pm

Yes thank-you,

Will investigate

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

Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Re: Display testing

Wed Oct 14, 2015 1:03 pm

gsh wrote:Yes thank-you,

Will investigate

Gordon
In addition to above issues, the touch capability locks up after a few days of running. The display is fine. Rebooting does not fix Touch, only a power cycle fixes it.

jamesh
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Re: Display testing

Wed Oct 14, 2015 2:37 pm

Dave31836 wrote:
gsh wrote:Yes thank-you,

Will investigate

Gordon
In addition to above issues, the touch capability locks up after a few days of running. The display is fine. Rebooting does not fix Touch, only a power cycle fixes it.
Do you have a dmesg or videocore log from after the lock up?
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Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Re: Display testing

Wed Oct 14, 2015 5:07 pm

i have a dmesg log... not sure if it is 'after' the lockup.

it is here: https://s3.amazonaws.com/Cauzway/dmesg

Dave31836
Posts: 19
Joined: Fri Oct 03, 2014 9:44 pm

Re: Display testing

Fri Oct 16, 2015 1:36 pm

UPDATE: Touch lockup only occurring on one of the three systems under test -- suspecting a hardware issue. Other probems previously re-ported occurring on all three systems.

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