Why Serial *in* on GPS?

[swatson999]

A buddy and I were talking GPS pucks (the 250 and the soon-to-be-released 2020), and this question came up.

Why do the pucks have both serial out AND in? What would be the purpose of a serial IN line on a GPS puck? Also, the SV configuration in Sec. 8 of the installation manual even shows the port configured for NONE for Serial Out on Port 5.

So why is it there? Symmetry?

 

[Dynon]

Theoretically software updates, but we've never had the need for one with the SV-GPS-250. We could reasonably confidently delete those wires from that product. With the SV-GPS-2020 being new (well, not even yet), we'll probably keep the wiring the same for that as well in case we learn something that causes us to need to update the software on it.

 

[swatson999]

Ah, that makes sense. I guess since it's never needed updating, I just assumed it wasn't even possible (e.g., PROM rather than EEPROM).

Good to know! Thanks!

 

[swatson999]

Just out of curiousity, which of the GPS signals does the new GPS puck receive and track? L1, L2, L2C, L5?

 

[Dynon]

Just L1.