STMicroelectronics announced a USB software Developer Kit for the STR7 and STR9 microcontroller families for the implementation of embedded software to handle the USB interface standard. Both of ST's 32-bit ARM-based STR7 and STR9 MCU families include many variants with USB ports, alongside a broad range of other standard interfaces. The USB Developer Kit - which will be available to users as a free download from ST's website - supports STR71x and STR91x devices with USB, as well as the STR75x family. It allows software development for all the USB transfer types, and includes an implementation of DFU (Device Firmware Update) to provide the capability to update system firmware through the USB interface. The kit also includes a 'Virtual COM' demo (CDC class) to emulate the classic RS232 interface on USB, for users that want to benefit from the ubiquity of USB, but retain legacy software. The software kit includes a library of drivers, plus demonstrations of each transfer type, to help users develop their own USB routines on STR7 and STR9 MCUs. An HID (Human Interface Device) mouse/joystick driver demonstrates fast response Interrupt transfers; high-speed Bulk transfers are illustrated with a mass storage application; and guaranteed speed isochronous transfers are supported with a voice/speaker/microphone demonstration.

The kit adds to USB software already available from third parties. USB stacks from third-party software companies are available to provide file system support, secured file systems, support for any real-time operating system, support for special devices and custom drivers, and support for composite devices that mix several USB classes. Some third-party providers also offer maintenance and support contracts.Both of ST's 32-bit ARM-based STR7 and STR9 MCU families include variants with USB ports, in addition to a wide range of other standard interfaces. These devices are fully USB compliant, certified and registered on USB.ORG.