Odd EFIS problem

[rainier]

anybody having the rebooting problem...

It's been difficult to get a system to do this here due to lack of information on circumstances.
Eventually I got some more detailed information from a customer with the problem, a video and a wiring diagram. Armed with this I could simulate the issue. However, this only happens with "lite" versions incorrectly configured or wired.

It is related to the iEFIS extender. It is enabled in the setup but is either not connected or connected incorrectly. In the above case the extender was connected to both panels in a master/slave connection (i.e. the extender was connected to both RX and TX lines on both panels). This cannot work and the result is that any TX from the extender is never seen by the EFIS.

The problem happens because the EFIS is trying to initialize the extenders serial ports - at the same time it configures the devices you have selected for the ports and sets initial states - this depends on the device you have selected in the serial port routing setup menu.
The setup of the ports does not get the expected acknowledgements and a few seconds later the EFIS will try again - this repeats endless. Everytime this happens device states are reset - this can cause undefined behavior. The exact effect is very dependent on circumstance and your systems individual configuration but one thing stands out - the GPS becomes intermittent and in severe cases the system crashes either immediately or after some time. In a case I could simulate here - the GPS status would show a red cross after all was OK and a second later the system would reboot.

As a result of this the system has been hardened to handle this case by gracefully shutting down the serial ports and any related drivers before re-initialization attempts. The updated code is here: www.mglavionics.co.za/Beta/EXP3.BIN
I make this available to the affected customer and another one but never received any feedback afterwards so please give this a try.

To recap - this fix affects "Lite" systems only - if you have a problem like this with a normal system that has an ibox if will (likely) not have an effect - but trying it will not hurt.

[rainier]

The iEFIS extender should be connected to the master EFIS only. It is however possible to connect the TX from the extender to both panels RS232 port 2 RX lines. This allows things like AOA and analog inputs to be seen by the slave EFIS.

While you can generally share RS232 ports between master and slave EFIS this does not apply for the Extender. It uses a data rate that is very high by serial port standards and the additional loading caused by the inactive TX line from one panel causes the signal from the other panel to get severely compromised.

There is a possibility to use one of the extender output ports (you have 5 of them) as a port to the slave panel should it become desirable to have the extender be fully usable from either source but this has not been implemented at this stage. Let me know if there is demand for that - if yes I can add it.

[royerm]

Will drop in to the hangar, 15cm of snow is on the way and I will get back to you on this for sure..
Thx

[huntwing]

Installed 1.1.2.2 a couple of weeks back to Challenger lite. No issues with re-boot but on several occasions at start-up there was no GPS despite fact there were at least 10 green satellites showing . Re boot and GPS status fixed immediately. Rolled back to 1.1.2.1 and it appears all good again.

[royerm]

Huntwing.... do you have an Extender connected??????

[royerm]

Here how it goes.
I'm in a hangar for the winter so no GPS fix for me.
I installed the version that Rainer released for us 1.1.2.3(beta) and the reboot is not happening... Yeaaa.

I had my transponder (Uavionix declared as Sandia) connected to the Panel on Port2, so I connected my Extender(RX1,TX1)
to the Panel Port2 and the Transponder to the Extender Port2 as Sandia transponder.
It doesn't have an X on the Transponder but if I try to for example to change the Mode to ON it comes back to Stdby..

There seems to be something happening that doesn't make it right with the Extender....

Wondering what baud rate is it set to when I pick Sandia Transponder on the Port2 of the Extender..
Is it the same as the Baud rate that was getting set on the Panel Port2 baud rate?????

Regards
Michel

[royerm]

Hello all.
The reason my Transponder connected to the Extender was acting-up is that the TX from the Extender
going back to the iEFIS was pulled out from my connector, as Rainier said a bad connection.

With everything well connected now I will try putting back 1.1.2.2 and see if it will power on/off as before
and conntinue with my WIFI gateway installation...

[huntwing]

No extender

[GeorgStein]

Hello,
I have a Discovery Lite with an extender. The extender is correctly connected and set up as described in the manual. The Extenders serial ports are not used. With version 1.1.2.2, the system is regularly rebooted. The GPS status would show a red cross after everything was OK and a second later the system would reboot.
With beta version 1.1.2.3 the system is stable again.

[gd5362]

I too had problems with 1.1.2.2 , I would lose the RDAC and extender on my challenger lite. Re-booting would occasionally work. So far 1.1.2.3 has corrected the problem, testing continues...