DI2 newbie... Boy do I have questions
 

Do I need EW-WU111 with EW-RS910 to have the ability to use the features of the Garmin? I see the EW-RS910 junction A has blue tooth. Can I use the Ultegra 8050(?) shifters "hidden" button to (for instance) change screens on the Garmin? Will the DI2 gear displays on the Garmin work via blue tooth? Do I need ANT+ from the EW-WU111 for any of this? The new bike has been delivered to the shop, and I dont get to see it until it is assembled, and of course they are way behind.... but I want to be ready for when it is ready. Why does it have to be so confusing??:bang:

EW-WU111 adds Bluetooth and ANT+. EW-RS910 has only a charge connection for the BCR2, but the BCR2 can be used with a Windows PC and the Shimano E-Tube Project software. In other words, the BCR2 is both a charger and PC adapter. With the WU111, yes, Garmin Edge computers will show gearing and Di2 battery status. It also allows you to assign functions to the top buttons on the shifters. It works with either BT or ANT+. The WU111 can also pair to a phone and lets you use the Shimano E-Tube phone app to configure and customize (though I personally found that so unreliable I always use the BCR2 and a PC).

SOOO why does the EW-RS910 have blue tooth instructions? AND, can all of the things I am asking about setting up be done via PC connection to the BCR 2 (cannot find info about this one)

You hold the button on the RS910 to make a BT connection between your phone and the WU111. Yes, the instructions are poor.

AHHH I never would have gotten that from reading the instructions. Poor indeed. thanks sfrider :foo::thumb::)

EDIT:
So, one last (maybe) question. To use the top buttons and to get the gearing to the Garmin, I DO need the EW-WU111... have I gotten that right?

Yes, you either need the WU111 unit installed inline on an E-Tube cable, or and if you are not wedded to the 910 unit, you can install on the handle bar, the SC-MT800 XT display unit. It gives you 3 E-Tube ports, a display of battery as well as current gearing, and has a built in BT WiFi unit, so replaces both the A-Junction as well as the 111 unit. Saves about $100, as you don’t need the extra cable to plug in the 111 unit as well the 2 separate units. Does clutter up the bar a bit.

Would add it is well worth it.

EW-WU111 = Well worth the money.

What I did once I got my bike was to grab a stool, sit down next the bike in the garage, connect with the E-tube software on my phone and just started playing around with it. It took a while and a lot of trial and error but eventually got everything figured out. Once you get to that point it is pretty easy. You'll never get there by trying to follow the very poor Shimano instructions.

Lots of good info at The Di2 Center

I found this as a valuable guide. Like others have said, the eww01 is key. Note that to get there it may require a battery upgrade.

Edit- I can’t post links yet sorry :(
search for di2 compatibility chart.

I spend money quite freely on bike gear, but I've never wanted this. I have 9000 series Di2, with R785 levers, so remote shifting isn't possible, and have no interest in the Di2/Garmin features.

YMMV.

Thanks all for the help. I love tech, and having all my data captured, so I guess this is a must to capture my gearing and shifting data. leo95se , this is a new bike, comes with DI2. I haven't seen it, but it should have the latest and greatest DI2. Steve B. I picked a bike with integrated (hidden) front end, so.... nope. thanks though!

That’s a nice way to set this up, wish my frame had it, but it’s 5 years old now.

Just to clarify:

SM-EWW01 is the previous generation unit, it does (private) ANT only. It will work with any battery / battery mount
EW-WU111 is the 2-port inline wireless unit. It supports BluetoothLE and ANT. You need BT-DN110 or BM-DN100. You do not have to connect both ports
EW-WU101 is also a current generation wireless unit. It is installed on the seat stay, near the RD. It supports BluetoothLE and ANT. You need BT-DN110 or BM-DN100.