AT91SAM7S and Android help you bang bits

There are plenty of test instruments (oscilloscopes, logic analyzers, spectrum analyzers, etc) where you plug some hardware into your laptop's USB port, and the laptop screen shows a display that would have appeared on a cathode-ray tube in decades past. It's very cool that we can do this, and these USB instruments are much more affordable (and much much easier to carry) than the old-school stuff that I grew up with.

The BluetoothBitBang is a gadget that comprises two boards from Sparkfun Electronics. One is a AT91SAM7S-64 header board, the other is a Bluetooth serial interface. You can see there are also some AA batteries in there to power the thing. This connects over Bluetooth to your phone, running a free app available on the Android Market. You can use buttons on your phone's screen to set or clear six output bits, and you can read six input bits. The two boards cost $71, and if you're willing to do some fine soldering and use the bare version of the Bluetooth module, you can knock off twenty bucks. If I'm energetic, maybe I'll see about putting together some kind of significantly cost-reduced version. That might depend on the level of interest I see in the thing. I've posted a Wikipedia page with a lot more information, including the schematic of how the boards are wired up.

The SAM7 firmware and the Android app source code are both publicly available on Github. I'm an Android fan, but the Bluetooth protocol for talking to the board is quite simple and if anybody is interested in writing an iPhone or BlackBerry app for the thing, I'll be happy to provide some support to make that relatively easy.

I think this whole thing gets a lot more interesting when (1) you move from a phone to an Android tablet, which will be cost-effective as tablets flood the market over the next year or two, and (2) start building much more sophisticated data acquisition front-ends. This is just about the simplest acquisition hardware I could imagine that would still be worth the effort of building and debugging it, but no reason one couldn't do a Bluetooth-connected oscilloscope or logic analyzer.

Android app: a timer for Sprint 8 workouts

I recently learned about an interesting exercise technique called Sprint 8, promoted by a guy named Phil Campbell, due to my sister's interest in Joseph Mercola, a doctor who took an interest in Sprint 8. The idea is pretty simple. Pick a favorite exercise, maybe a stairmaster or a stationary bike, and do eight sprints in the following way. Remember to consult your physician before starting any exercise program.

• Do two or three minutes of warm-up, nothing too strenuous.
• Push yourself for 30 seconds. Work as hard as you can without risk of injury. This is a "sprint".
• For 90 seconds to 2 minutes, move to a slower easier pace. Catch your breath. This is called "active resting".
• Do a second 30-second sprint, followed by another 90-to-120-second active rest.
• Repeat until you've done a total of eight sprints.

The Android app is a timer for doing Sprint 8, and the source code is posted on Github. If you're set up for Android app development, feel free to compile it and try it on your Android phone. The app is now available in the Android Market.

There's a lot of exercise physiology knowledge to Sprint 8 that, in all honesty, I haven't yet studied. Maybe I will in future, and possibly blog about it. But I do know that after just a couple of short Sprint 8 workouts I feel really good. My back pain is way down and I get less winded when I climb a flight of stairs. Sprint 8 workouts are claimed to produce human growth hormone (the stuff outlawed in Olympic and professional sports because it gives athletes an unfair competitive advantage) which appears to have anti-aging effects. Also see "interval training", believed to work well for fat loss.