Another Reason to Beware Bargain Basement Bluetooth

I was debugging a Bluetooth-related problem on a Windows 7 machine recently, and I found another great example of why sometimes you get what you pay for, even when buying something as nominally standardized and homogeneous as a Bluetooth adapter. It so happens that this machine was using one of these $5 adapters with the fake antenna: That was the first thing I noticed about these adapters. The second was that each and every one of them had the same... Read More

Cheap and easy Android to Propeller bridge

This is a quick plug for a spiffy project that M. K. Borri (spiritplumber) has been building using my usb-fs-host object. He’s connecting an Android phone to a Propeller microcontroller, emulating the ADB debug protocol on the µC, and using this as a communication bridge in order to control robots from the phone. He has a video to demonstrate his progress: This project is actually remarkably similar to the IOIO, but actually his was announced... Read More

Propeller Bluetooth Stack Demo

After going months without a lot of time for working on my hobby projects, I finally had a few free days to work on debugging my embedded Bluetooth stack for the Propeller. I got it working well enough to demo a Serial Port Profile device, implemented using only a Propeller Demo Board and a $2 USB Bluetooth dongle. Original blog post More about the bit-banging USB host Forum thread Source code  Read More

It’s Alive: Bit-banging full-speed USB Host for the Propeller

I’d like to make a more detailed post about this once the project is a bit further along… but for now just a brief description and a couple teaser photos This is one of those things that people have said was impossible, and I’ve wanted to try it for a while. I finally found an excuse. I wanted a way to build more cheap wireless networked devices. You can get bluetooth and wifi adapters that are microcontroller-friendly, but it’s... Read More

Announcing vusb-analyzer 1.1

The Virtual USB Analyzer is a graphical tool for analyzing USB sniffer logs. It can do some basic protocol decoding, and it has a graphical timeline view which helps to visualize the latency and concurrency characteristics of USB traffic. This release only adds a single feature, but it’s one that many people have probably been waiting for: support for Linux’s built-in usbmon sniffer tool. With usbmon, tracing all USB traffic on your system... Read More

“Luggable” power pack

Paul and I are leaving on a cross-country train trip next week, for Jen and Shawn’s wedding in Colorado. I’m sure the view will be great, and I’m bringing a handful of books- but Paul and I are geeks and we need our electro-doodads. If only we had a way to run our Nintendo DS and PSP for the ~30 hours that the trip will take… I sifted through my stockpile of junk, and came up with this: It’s kind of like a mega-size... Read More

Wireless temperature picture frame mashup

This is the latest geeky addition to our home decor. It’s a Kodak W820 digital picture frame, showing a graph of real-time temperature data collected from around the house: upstairs and downstairs, garage, outdoors, and even inside the refrigerator. More photos on Flickr, implementation details below… Temperature Sensors Most of my friends probably know that back in 2004, when I was still in college, I built a set of wireless temperature... Read More

Virtual USB Analyzer

From late 2005 to early 2007, I worked on the USB virtualization stack at VMware. We ran into all sorts of gnarly bugs, many of which were very hard to reproduce or which required access to esoteric or expensive hardware. To help with debugging problems both internally and with customers in the field, we added logging support to our virtual USB stack. Starting with VMware Workstation 5.5, if you set the right hidden config option we’d start... Read More

Random Update

Well, it’s been a while since I’ve updated. Nothing on its own recently has inspired me much to write, but I have some smallish things to mention. I have a new laptop on the way! My 700 MHz Pentium III with 192MB of RAM was just getting too clunky for day-to-day use. I recently ordered a Thinkpad T43 with 2GHz CPU, 1GB RAM, and SXGA+ 14.1″ display. It shipped Monday, and I can’t wait to start using a Real Computer. At work,... Read More