Thanks, I was wondering what that was for. I'd tried connecting to a USB power source thinking maybe the hub could charge one or two
batteries via USB power, but it didn't do anything. So I was figuring it was for firmware updating of the sled, but was having difficulty finding any documentation on it.
And yes, all of my
batteries updated while in my Spark via the DJI Go app. In fact,
it won't let you fly with a
battery that's got out-of-date firmware. Had to fight that unexpectedly after swinging by Best Buy on the way to the field to fly - picked up two
batteries, and ended up wasting a good half hour unexpectedly getting the firmware on them updated. (it's a slow process, and trying to follow the "instructions" on DJI's pages only makes things take longer until you figure out the
correct way to do it) So lesson learned - anytime you get a new
battery,
plan to have to update the firmware before you can use it. Also plan to charge it a bit. So that
battery will require a good 45 minutes or more of "prep time" before its first use. (also keep in mind... the update must occur
while installed in your Spark, so not only is the
battery down for 45 minutes, about 12 of those your SPARK is also down)