July 2003

Earlier this month I talked about the Microchip PIC16C745 and PIC16C765, which are 8-bit microcontrollers with built-in low-speed USB. Since that time, I’ve got hold of one of these devices and built a simple USB peripheral with it. Click on the thumbnail for a bigger version of the image.

Summary: hardware easy, firmware tricky, software painful. Read on for more detail and some hints for anyone treading the same road in the future.

[Last updated 20050606: added firmware source code.]

Please sit down.
I am going to tell you everything.
   — Albus Dumbledore, to Harry Potter

Well, Dumbledore may have finally come clean and answered all of Harry’s questions, but from a technical perspective I feel J. K. Rowling still has some explaining to do. Here are some areas she might consider addressing in the next volume.

Clay Shirky writes about the Internet, as much as a social and cultural phenomenon as a technical one. His recent article A Group Is Its Own Worst Enemy describes what happens when “social” software (Usenet, mail, instant messaging, weblogs, etc.) is used to support growing, long-lived user groups. In particular, he discusses patterns of failure in these groups and to a lesser extent what can be done to avoid group failures.

Fun devices of the month: Microchip’s PIC16C745 and PIC16C765. As well as the usual microcontroller features, these require only a couple of external components to function as low-speed USB peripherals.