Information about AUP, the AVR USB Programmer.

2006-11-22: I have just learned of a new project, "USBtiny". It sounds like it does more than my design did, all with clearly GPL-licensed software.

I am no longer working on this project. I encourage anyone who is interested to continue it.

The board is compact and one-sided, with an area less than 2 square inches and a short parts list. However, it provides:

• 10-pin connector, 5 pins minimum on slave for programming interface
• SPI interface programming for most AVR-family processors
• 3 GPIO pins to slave (SPI SCK/MISO/MOSI pins, tristated by default)
• +5V power supply to slave (up to 350mA with firmware modification)
• bidirectional serial interface to slave
• Jumper for firmware upgrade by programming cable (not self-upgradable)
• One LED indicator under USB control
• USB B receptacle for separate USB cable, or cut your own USB cable and solder to board directly

Programming speed is about 100 bytes/second.

Boards in the existing run are missing one trace. Its location is shown in the image on the right.

The patches to avrdude are only tested on Red Hat systems (RedHat 7.2, 9, and Fedora Core 1), but in theory can work on OS X and Windows thanks to the portability of libusb. My new AVR programmer software is tested on Linux and Windows XP.

Some links of interest:

• uavrp, my own AVR programming software
• avrdude, an AVR programmer
• Igor Cesko's hardware projects
• USB firmware with GPL copyright (Currently unavailable, but see usb90s23x3.asm below) Some have suggested that there are license problems with Igor Cesko's USB firmwares for AVR processors, and indeed the files from his site do not seem to be licensed under the GPL. The files from this site are.
• avrfreaks, one website with information for avr hackers
• atmel.com, the manufacturer of the AVR family of chips

The information below is a dumping ground of related files: The Eagle schematic and board files, plus png images of them. The firmware, suitable for assembly by avra. Patches to avrdude 4.0.0. Some photos of the assembled programmer. The pin assignment in the slave connector. Anything else I thought was relevant.