Close

...and in the beginning there was a heart rate monitor....

A project log for Watch with Bluetooth Host and E-Paper Screen

A watch that can host bluetooth devices and uses minimal power

power.supplypower.supply 12/09/2014 at 11:201 Comment

and it was good. But, on the next day, the man found that the heart rate monitor would not connect to his phone... and then, everything was bad.

G'day everyone. Just a quick update on the preliminary findings of my initial research. I've tracked down a suitable screen on ebay (Link) for the watch. But it has to come from China, which could take too long (I'm open to suggestions to an alternative in the 1-2 inch size as well).

I'm looking at using this bluetooth module because it supports the Bluetooth V4.0 Low Energy specification, which will reduce battery usage considerably. It also has the BlueRadios stack preloaded on it. That way I don't have to buy a dev kit to program it myself, it just accepts commands via the AT command set ( more information here, pdf warning).

I'll be using the 3V Trinket Pro to run everything, that way I don't need a boost converter to power it and it will require less power to operate.

Since this is in the form of a watch, I have thought about including a Real Time Clock module to keep time. But, I haven't done any research on this front as of yet.

The picture I've uploaded is just a quick drawing I did in Inkscape to get a better idea of what it would look like when completed. So, please don't judge the shoty rendering ;). I will probably have the band taper so it isn't as wide at the bottom. But, I didn't show that here, mainly due to my lack of industrial design skills when it comes to using Inkscape.

Anyway, it was great to get some of this out of my head and into the world. Don't forget to hit the comments section to share your opinions, offer some support or even to tell me where to go.

Discussions

power.supply wrote 12/09/2014 at 11:23 point
Oh, I forgot to mention that I'll be using a Li-Po battery to power it all and hopefully design some kind of snazzy magnetic connector for charging to reduce the overall size of the device.

  Are you sure? yes | no