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I just got into Bluetooth LE as an Android developer. My school background is in embedded devices, so I wanted to see what's out there that I can program on the

I just got into Bluetooth LE as an Android developer. My school background is in embedded devices, so I wanted to see what's out there that I can program on the device side, and then connect to the phone. There are two comparable offerings for Bluetooth LE chips (are there others? let me know): the Texas Instruments CC2541, and the Nordic Semi nRF51822. They can be purchased as development kits for $100, but the chips only cost $2-3 in larger quantities, so you could take something based on them to production without the cost being prohibitive. I like the TI SensorTag (CC2541 based, $25). It comes with several sensors a coin cell battery, and iOS sample code, which is neat. http://www.ti.com/tool/cc2541dk-sensor http://www.ti.com/tool/cc2541dk-sensor On the other hand, if you wanted to program the bluetooth device itself, the CC2541 isn't ideal. It's based on the 8-bit Intel 8051 micro controller, and TI's radio libraries only work with the very expensive and crappy IAR tool set. I bought their development kit for $100 before realizing that it's worthless without the $3000 IAR IDE :| The Nordic Semi nRF51822 development kit is much better. Their chip is based on the ARM Cortex M0, so you get a tiny 32-bit processor. It comes with a programmable USB dongle that can be used right away, as well as a J-Link Lite CortexM-9, which can download code and do full GDB debugging on the device. You may need to be comfortable looking at schematics to figure out the other two included demo boards, however. http://www.nordicsemi.com/eng/Products/Bluetooth-R-low-energy/nRF51822-Development-Kit http://www.nordicsemi.com/eng/Products/Bluetooth-R-low-energ... If anyone knows of any other Bluetooth LE chip offerings, please let me know (I've read that Broadcom has 'announced' several chips, but I didn't see anything concrete that's shipping at the moment). The Bluegiga modules are too integrated for me, and too expensive to sprinkle them around the house for random sensing/controlling projects, but they may be easier to get started with as well.

vitovito 13y ago
Remember, too, that another recent iOS 7 device can also run as a BTLE "client" and pair: that's how testing iBeacons works. You can pick up an iPod Touch and write an app for it that uses the Touch's sensors to do what your custom hardware could do, to get further than you might if you had to start from hardware alone. Additionally, integrating new sensors into the Touch could be done more simply via the headphone jack using an Arduino: http://www.creativedistraction.com/demos/sensor-data-to-iphone-through-the-headphone-jack-using-arduino/ http://www.creativedistraction.com/demos/sensor-data-to-ipho... or using Project HiJack: http://web.eecs.umich.edu/~prabal/projects/hijack/ http://web.eecs.umich.edu/~prabal/projects/hijack/ Once you've got a version using an iPod Touch and a custom sensor working, you'd have a complete test case and prototype to develop original hardware against.
- dschuler 13y ago
  I wasn't aware of iBeacon, thanks for the tip!
jamesbritt 13y ago
Do you (or anyone else) know a decent Bluetooth dongle that works on Windows 7 and will find and pair with LE devices? I picked one up last week before a local hackfest, but in a room of a half-dozen BLE devices (one about 10 inches away) my laptop detected zero. Could very well be I was doing something wrong but it seems there shouldn't have to be a whole lot to do after plugging it in and loading the drivers. I think I just got the wrong thing. (It's a Kinivo BTD-400 Bluetooth 4.0 USB adapter.)

vitovito 13y ago

Remember, too, that another recent iOS 7 device can also run as a BTLE "client" and pair: that's how testing iBeacons works. You can pick up an iPod Touch and write an app for it that uses the Touch's sensors to do what your custom hardware could do, to get further than you might if you had to start from hardware alone. Additionally, integrating new sensors into the Touch could be done more simply via the headphone jack using an Arduino: http://www.creativedistraction.com/demos/sensor-data-to-iphone-through-the-headphone-jack-using-arduino/ http://www.creativedistraction.com/demos/sensor-data-to-ipho... or using Project HiJack: http://web.eecs.umich.edu/~prabal/projects/hijack/ http://web.eecs.umich.edu/~prabal/projects/hijack/ Once you've got a version using an iPod Touch and a custom sensor working, you'd have a complete test case and prototype to develop original hardware against.

dschuler 13y ago
I wasn't aware of iBeacon, thanks for the tip!

jamesbritt 13y ago

Do you (or anyone else) know a decent Bluetooth dongle that works on Windows 7 and will find and pair with LE devices? I picked one up last week before a local hackfest, but in a room of a half-dozen BLE devices (one about 10 inches away) my laptop detected zero. Could very well be I was doing something wrong but it seems there shouldn't have to be a whole lot to do after plugging it in and loading the drivers. I think I just got the wrong thing. (It's a Kinivo BTD-400 Bluetooth 4.0 USB adapter.)