SystemMetrics Error

Hello everyone,
I am new to gadgeteering and I am developing using FEZ Cerebus hardware with Display_N18 module. My application displays simple WPFwindow on the display module.
It was working pretty well and now the same code gives me this error;
“System reboot should have occurred to set width/height in SystemMetrics” and execution halts.

I removed every bit of code and even with simple “Window win = display_N18.WPFWindow”, it throws the same problem.Any thoughts on whats causing this and how to get rid of this?


I’d guess that something gone wrong when the screen size was written to flash.
I would update the firmware again, to have a clean restart.

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@ ReinhardOstermeier
Thanks for your response. I updated the firware using MFDeploy. That did not help.
I have noticed that it is this line that is causing the problem:
Window win = display_N18.WPFWindow;

i can still write text to the display using the native method and it it works

Any idea what else I could try?

The Gadgeteer WPF code in 4.2 assumes an LCD configuration. Since the DisplayN18 does not use the LCD controller, the WPF initialization code fails. The only sort-of work around I see is to add the Gadgeteer core DLL to your project and remove line 197 in DisplayModule.cs:

 SystemMetrics may be used elsewhere in WPF so it may still fail in other places. SimpleGraphics is your best bet on the N18.
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Thanks Aron. That answered the question :-).
I should say that I had this trouble with Display)N18 module only with Cerebus. On my raptor, even the WPFWindow worked as expected.