So, how to get the numbers off of the Dexcom and send them to a "smart" watch ? Additional bonus, the Dexcom can be safely stored somewhere near by and better protected from destruction when I'm on a dirt bike ride. Also the form factor of the watch, allows me to keep track of the numbers when I'm kickboxing, since the monitor won't survive a hit. Also, the smart watches are about half the price of a Dexcom unit, so they can be sacrificial. The one I'm starting with is 1/10th the price.
Texas Instruments has an interesting product, the eZ340-Chronos, that's been out for a while. I purchased one from Sparkfun. The goal for the watch is to be able to send a number to it. After a lot of time on Google, it became clear that the intent of the watch is to send limited information, not receive it. The only receive mechanism that appears it would work, ie. display a glucose reading , real time, is the BlueRobin heart rate monitor component. The BlueRobin component isn't part of the watch that's really meant for developer customization. A demo app for the Chronos, "Control Center", includes a sample program that sends "fake" heart rate values to the watch, exactly what I want.
Sending Hex "FF 02 03", starts BlueRobin .
Sending Hex "FF 05 04 XX" sends a number to the watch. Where XX is the Hex representation of the integer I want to send.
Success, I can send a number to the watch, now to get the number!