Dynon EFIS / EMS wiring glitch w/upgrade

[SFB711]

Dynon Users

This might save you some time trouble shooting.
If you have a EFIS 100 and a EMS 120
If you have pre wired the DSAB pins
If you have upgraded to the new software
If you have been using a gender changer (serial to serial connector) so the two units talk to each other
And now it don't work????

After installing the new software upgrade on both units, my EMS would talk to the EFIS, but the EFIS would not talk to the EMS. After consulting with Dynon they will tell you to connect Pin 10 of the EFIS to pin 12 of the EMS via the serial connector. That is only half the story. If you wired per their instructions (my manuals are dated Aug '05 for the EFIS and Jan '06 for the EMS) Pin 10 on the EFIS is pin 2 on the serial connector. Pin 12 on the EMS is pin 3 on the serial connector. They obviously miss each other. I got rid of the gender changer and just hard wired between the serial connectors using a 22awg wire and some male D pin connectors. Didn't want to mess with re-pinning the serial connectors since I'll need them for the next upgrade download. I wish they would have pointed this out! This might save someone some time. Newer manuals may have different wiring instructions, and supposely the next upgrade will eliminate the need for the serial connectors for data transfer all together.

Hope this helps.

N322SF

 

[647jc]

My EFIS-D100 installation guide is dated 10/4/2006 and it shows the optional connection to an EMS on page 2-4. The connection shows using a null modem AND a gender changer to connect the two DB9 connectors. They really didn't explain what the null modem was but I assume it is a crossover of pins 2 and 3 so xmit and receive will be connected properly between the two devices (xmit to receive and receive to xmit), the ground signal pin 5 should go straight through. So, I think my manual is showing correctly what you described you had to do to get it to work.

 

[N941WR]

... but I assume it is a crossover of pins 2 and 3 so xmit and receive will be connected properly between the two devices (xmit to receive and receive to xmit), the ground signal pin 5 should go straight through.

That is exactly what the null modem does.

Once both the DSAB and serial connections are made, you can share info back and fourth between the two units.

Keep in mind, Dynon is working on doing all the data sharing over the DSAB conection so, some time in the future you might be able to dump the serial connection.

 

[Dynon]

This looks like an issue with using older manuals. Whenever you update our software, you should also grab our latest install and user guides off of our web site. The connection you describe wasn't really supported back in '05/early '06, so it's not in those manuals.

Also, we've supported the data via serial and DSAB for a while now. It's not just this last update that added it. If it was working before, it will keep working. Nothing about the wiring requirements has changed in about a year.

Our next update in a few months will delete the need for the serial connection. All data will go over DSAB.