We are - just like plenty of other EFIS users before here in the forum - looking for a option to always supply pressure (standard, 29.29/1013) altitude on the Encoder serial transmit (EFIS DB25 pin #13, GND #21), regardless the baro settings.
Assuming the displayed altitude is software calculated based on the baro settings, it should not be that difficult to maintain both altitude numbers in the system.
Here what the EFIS-D100 Installation Guide, P/N 100478-000, Revision E, For use with firmware version 5.0, says:
http://www.dynonavionics.com/downloads/Install_Guides/EFIS-D100%20Installation%20Guide.pdf
"Altitude Encoder Wiring
The EFIS-D100 outputs its altitude measurements in one of four standard serial
outputs and is readable by many modern transponders. The EFIS-D100 will function properly whether or not this altitude encoder functionality is used. To use the EFIS-D100‘s altitude encoder functionality, simply wire the 2 encoder connections (GND and Encoder Transmit) from the DB25 connector to their respective connections on your transponder.
Per ATC/FAA requirements, the serial encoder output of the EFIS-D100 reports pressure altitude, which, by definition, is indicated altitude when the baro is set to 29.92. So, when you set your EFIS-D100‘s baro adjustment to 29.92, its indicated altitude will match the altitude that is being reported to your transponder"
The actual implementation does make the encoder output of the EFIS virtually useless. When flying in lower airspaces, CTR, ATZ or similar, all traffic has to switch to QNH - without interfering or falsifying the transponder altitude - especially in the Mode S environments. Currently, the only work-around is to install an additional, independent serial encoder, adding weight and unwanted complexity.
Thus, we kindly ask Dynon Avionics to add a set-up option (not to change the default or previous behavior), allowing to set the encoder serial transmit on pin #13 to standard 29.29/1013, regardless the baro settings.
[edit]
Or can Dynon Support confirm - regardless various postings in the forum here - the encoder altitude is always standard based on 29.29/1013 and does not change when altering the baro scale on the front end?
[/edit]
Greetz,
-Kurt.
Experimental Aviation of Switzerland
SportAviation of Switzerland
Czech Sport Aircraft factory representative for A, CH, D
Assuming the displayed altitude is software calculated based on the baro settings, it should not be that difficult to maintain both altitude numbers in the system.
Here what the EFIS-D100 Installation Guide, P/N 100478-000, Revision E, For use with firmware version 5.0, says:
http://www.dynonavionics.com/downloads/Install_Guides/EFIS-D100%20Installation%20Guide.pdf
"Altitude Encoder Wiring
The EFIS-D100 outputs its altitude measurements in one of four standard serial
outputs and is readable by many modern transponders. The EFIS-D100 will function properly whether or not this altitude encoder functionality is used. To use the EFIS-D100‘s altitude encoder functionality, simply wire the 2 encoder connections (GND and Encoder Transmit) from the DB25 connector to their respective connections on your transponder.
Per ATC/FAA requirements, the serial encoder output of the EFIS-D100 reports pressure altitude, which, by definition, is indicated altitude when the baro is set to 29.92. So, when you set your EFIS-D100‘s baro adjustment to 29.92, its indicated altitude will match the altitude that is being reported to your transponder"
The actual implementation does make the encoder output of the EFIS virtually useless. When flying in lower airspaces, CTR, ATZ or similar, all traffic has to switch to QNH - without interfering or falsifying the transponder altitude - especially in the Mode S environments. Currently, the only work-around is to install an additional, independent serial encoder, adding weight and unwanted complexity.
Thus, we kindly ask Dynon Avionics to add a set-up option (not to change the default or previous behavior), allowing to set the encoder serial transmit on pin #13 to standard 29.29/1013, regardless the baro settings.
[edit]
Or can Dynon Support confirm - regardless various postings in the forum here - the encoder altitude is always standard based on 29.29/1013 and does not change when altering the baro scale on the front end?
[/edit]
Greetz,
-Kurt.
Experimental Aviation of Switzerland
SportAviation of Switzerland
Czech Sport Aircraft factory representative for A, CH, D