Trying to free up a serial port

[jacktunnell]

Can I put a selector switch to choose which GPS2020 I want to send to both screens? 4 pole, single throw? What about 2 pole, single throw and just switch the TX & RX?

With everything powered up would there be any induced problem(s) from switching between the GPS sensors. I currently have both going to each screen. I currently have an ACK E-04 ELT using the TX on one port. Can this piggyback on the TX of the GPS2020 port?

 

[Dynon]

Right now you can't split the SV-GPS-2020 port in half. It runs at 115200 baud, and SkyView only supports the same baud rate for both halves of a serial port even if you could split it like you can for others.

You'd see a momentary loss while you switch, but your solution would basically work.

One thing you can do is have each of them serve a screen exclusively. You lose a slight bit of GPS position redundancy, but you'd still have dual GPS receivers.

What are the other devices on your serial ports? Maybe there's some other port you can split for the ACK?

 

[jacktunnell]

ADSB - - - - - - - - -Port 3 PFD & MFD
Transponder 261 - - Port 1 PFD & MFD
VPX - - - - - - - - - - Port 4 PFD & MFD
GPS 2020 #1 - - - - -Port 5 PFD & Port 2 MFD
GPS 2020 #2 - - - - -Port 5 MFD
ACK ELT E-04 - - - - -Port 2 PDF

The ports are already overused as the #2 GPS2020 only inputs to the MFD.

I want to add a Garmin SL30.

Idea #1 is install a switch to select which GPS2020 sensor to be used.

Can I just switch TX & RX or do I need to switch Pwr & Gnd also. They are both receiving Pwr & Gnd from both screens off of pins 24 & 29. I would run TX & RX from the selected GPS2020 to port 5 on both screens.

That would free up Port 2 on each screen if I lose the ELT GPS position input. Don't like losing that.

Idea #2 is ????

 

[jacktunnell]

OK, I can use the GPS output of my Garmin 396 for the ELT so what I really need is info on using my GPS2020s one at a time and what must be switched.

The question is, will it hurt a GPS2020 if it has power and ground but the TX & RX are open?

I either need a --
2 pole, 2 throw
or
4 pole, 2 throw

 

[Dynon]

You can switch only the data lines, as you suggest. You won't hurt it by having power continuously on.