Here are some photos of the SparkFun AVR Stick, which at $9.95 provides a very inexpensive USB solution, based on the ATtiny85. This board is using a software stack to emulate a USB 1.1 device interface, in particular the V-USB stack (formerly known as AVR-USB) from Objective Development under GPLv2 or under a commercial license. I’ve seen the V-USB stack used by a couple projects recently, seems to be gaining some mindshare among the DIY crowd.
As you can see the board I have is tiny, yet still manages to provide headers for all 8 of the ATtiny85s pins in addition to a 6-pin AVR ISP connector. On the board I have, there is some spotty-looking structural solder on the USB connector contacts, but the board otherwise looks clean and seems to work fine. The board comes pre-programmed with a data-logging application that reports readings on two ADC channels to the host as a USB HID report. And as SparkFun happily points out, “This thing is meant to be hacked!” Full source code is available under an open license, which builds cleanly and looks to be reasonably easy to repurpose.
Post a Comment