This page contains GPL'ed drivers for AnchorChips EZUSB USB Microcontroller
Target Firmware example: target_example.tar.gz 67kBytes
Host Program example: bayusb.tar.gz 162kBytes
Diff for sdcc's assembler: asxxxx.diff 1kByte
You need to have usbdevfs mounted somewhere. Note that the tools haven't been updated for usbdevfs, but it should be quite trivial to do so.
The target firmware example can be compiled with then sdcc C-Compiler. The diff file for the assembler included in sdcc makes the assembler recognize relative jumps to targets out of range, a vital feature for assembler programmers. The makefile generates an intel hex file containing the firmware image.
The host program example contains everything needed to download and run the firmware on the AnchorChip device. It includes a program that converts the intel hex file into a C header file that can be included in the program. Also, it contains an internal USB request abstraction interface and an implementation of that interface for the Linux kernel driver mentioned above and for AnchorChips generic driver for Windows. It can be crosscompiled into a Windows binary using i386-mingw32-gcc.
Have fun