System.NullReferenceException

[oldgraybear]

I just got this error:
System.NullReferenceException: Object reference not set to an instance of an object
at System.DateTime.get_Now () [0x00000] in <filename unknown>:0
at System.Timers.Timer.Callback (System.Object state) [0x00000] in <filename unknown>:0
at System.Threading.Timer+Scheduler.TimerCB (System.Object o) [0x00000] in <filename unknown>

Running 3025 on a Raspberry PI 2b with a Ambient ws-2080

MXdiags.zip attached

Don

[steve]

It's a bug in Mono. Which version are you using, the default 3.2.8, or the later 3.10 that is available for the Pi 2?

It may not be causing Cumulus any problems, it's happening on a timer tick, so it probably just means that one won't run but there will be another along shortly.

[oldgraybear]

I am using 3.10 It did seem to continue on but when i tried to reboot the whole thing locked up.

Thanks Don

[mcrossley]

I did come across a post that enabled the use of later versions of mono on the Pi2 only. The binaries are not compatible with the Pi as it uses a different processor. I don't know if this is still relevant, or if it works with MX - just a point of interest in case people weren't aware.

Code: Select all

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF 
echo "deb http://download.mono-project.com/repo/debian wheezy main" | sudo tee /etc/apt/sources.list.d/mono-xamarin.list 
sudo apt-get update && apt-get upgrade 
sudo apt-get install mono-complete

Experiment at your own risk - I haven't got a Pi2 to test it on.

[steve]

Mark, I posted about that here - https://cumulus.hosiene.co.uk/viewtopic.php?f=27&t=13587

I think that's where 3.10 comes from.

[mcrossley]

Ah, sorry yes I'd forgotten that post, it should install 3.12.1 though?

[pete_c]

I have had issues with most current version of Mono on the RPi2 running other software that utilizes Mono.

HomeGenie works fine with most current version of Mono at this time. Homeseer does not.

I have not tried the newest version of Mono on the CumulusMX RPi2.

I have locked mine at one version modifying apt sources.list file. Not sure if this will help the issue.

I also now use the PiFace RTC shim clock on my new RPi2's. (well now 3 of them).

# hwclock
Thu 16 Jul 2015 07:59:38 AM CDT -0.846765 seconds

uname -a
Linux ICS-Cumulus 3.18.11-v7+ #781 SMP PREEMPT Tue Apr 21 18:07:59 BST 2015 armv7l GNU/Linux

mono -V
Mono JIT compiler version 3.12.1 (tarball Fri Mar 6 23:28:08 UTC 2015)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. http://www.mono-project.com
TLS: __thread
SIGSEGV: normal
Notifications: epoll
Architecture: armel,vfp+hard
Disabled: none
Misc: softdebug
LLVM: supported, not enabled.
GC: sgen

adding these two lines to sources.list file locked me to Mono 3.12.0

deb hxxp://download.mono-project.com/repo/debian wheezy/snapshots/3.12.0 main
deb hxxp://download.webmin.com/download/repository sarge contrib

I also install Webmin on the RPi2's for checking on regular updates with RPi2.

BTW still testing by splitting the serial port using a mini serial server. It works fine unless I turn on debug.

1 - Davis Console = = > AVocation Serial server = = >
A - Windows Server 32 bit box running Cumulus
B - RPI2 CumulusMX.