Zephyr Bluetooth Heart Rate Monitor

I just received a Zephyr HRM - a heart rate monitor that sends its data to a PC or smartphone via Bluetooth. It was a reasonable $99 + $30 for FedEx Priority shipping from New Zealand to the States. It shows up as a Bluetooth serial port after pairing with a PC so it makes it very easy to development a .NET application for it. I've currently got code running to talk to the device, verify the integrity of the data packet (CRC) and update new heartbeat timestamps. I'll be using it to track my workouts at home. I may even get adventurous and try to write an app for my WinMo HTC Touch Pro phone, but that will be some time in the future.

BlueTracker Released

I'm releasing my BlueTracker application which tracks bluetooth devices and issues updates over xPL. It currently works with only the Microsoft BT stack, but you can hack your BT dongle to use the Microsoft stack. I don't have any Widcomm devices so it doesn't have any support for that driver - but it should be easy enough to add when the 32 Feet.NET SDK is released with Widcomm support (It's in Beta currently). You can read my previous posts on BlueTracker to get an idea how it works. Grab it.

Bluetracker Progress

I worked on my bluetooth tracking app a little more last night adding the capability to receive device updates from other BlueTrackers. I did this by adding xPL so that the app will generate xPL messages when it detects a phone or when that phone times out. Other BlueTrackers on the network, which may not be close enough to the phone to detect it, receive those xPL messages and can then update its list of present phones. My HA software can now key off phone detected messages from all BlueTrackers to establish that a phone is home. When a phone leaves the house, eventually all BlueTrackers will issue timed out messages, but only one BlueTracker will serve as a master - and only messages from that BlueTracker will be used to determine if a phone is no longer home. The app has been running on two machines overnight and is pretty much done.

New Bluetooth Project

I have been using xPL Bluetooth but it hasn't worked quite right for me so I've decided to write my own Bluetooth app to track our cellphones coming & going. I am using In The Hand's 32 Feet.NET PAN SDK. The example code had everything I needed to get a quick start writing my app. After a couple hours of playing around, I've got it up & running detecting some bluetooth devices. I've added code for tracking and timing out devices along with a debug window. Now, I need to decide if I'm going to add a configuration file and also how I will interface it back to my HA system. I originally wanted to add it to my xPL sCU application, which interfaces starCOMUltra, xPL, xAP, IM & UPB. Instead, I've decided on a standalone app as I'm not getting anywhere near the advertised bluetooth range - so I could end up with devices timing out if they get moved from the family room to the living room, etc. My plan is to put the app and bluetooth interfaces on all the servers around the house.

Bluetooth Antenna Hack

Even with the Cat-5 extension, the bluetooth adapter wasn't picking up our phones consistently. I ran across this site where the author soldered a wifi antenna onto the bluetooth dongle. My adapter is different - it has a trace on the pc board as the antenna - so i soldered the center wire of the antenna cable to that trace and soldered the shield to ground. I went one step further and put on a Windsurfer wifi antenna booster. Now, coverage is really good.

Bluetooth Proximity

I've been trying out Tony's xPL Proximty app and it's been working out pretty well. I was using a Java based blueooth app but I like Tony's app much better. With the USB bluetooth dongle in the server room, the range isn't very good, so I made a USB Cat5 extension. I cut a USB extension cable in half and terminated each end with a Cat5 keystone jack such that each wire took 2 connections in the jack. I connected the jacks with a 25 foot patch cable, plugged one end into the server and a powered USB hub into the other. Finally, I plugged the dongle in and it worked. Coverage was much better but I'm thinking of moving the dongle downstairs to be closer to the phones and that may be a little too far for this hack. There are some USB extenders I may look into later.