DirectFB is a thin library that provides developers with hardware graphics acceleration, input device handling and abstraction, an integrated windowing system with support for translucent windows and multiple display layers on top of the Linux framebuffer device. It is a complete hardware abstraction layer with software fallbacks for every graphics operation that is not supported by the underlying hardware.
Device::ParallelPort is a Perl API that allows low level access to the parallel port of most computers. It does this by using a number of drivers, which can be customized and added to, including Linux (direct and parport), Win32, Script, Dummy, and more. It also contains a number of direct access devices including an example printer and a relay controller card.
ServoMaster provides hardware independent abstractions to servos and servo controllers. It has implementations for several servo controller families, including Phidget, Pololu, Parallax, and SSC. It has support for servo and controller metadata, introspection, and capabilities discovery.
JTAG Tools is a software package which enables working with JTAG-aware (IEEE 1149.1) hardware devices and boards through a JTAG adapter. This package has an open and modular architecture with the ability to write miscellaneous extensions like board testers, flash memory programmers, and so on.
Linux device driver for CueCat barcode readers that supports multiple PS/2 CueCats on either the keyboard port, mouse port (without disabling the mouse) or USB port through a PS/2 -> USB adapter, or native USB CueCats. A standalone application that doesn't require the driver and also reads barcodes from a CueCat connected to a serial port through a homemade PS/2 -> serial converter is included as well. The driver separates CueCat barcode scancodes from normal keyboard or mouse scancodes, decode the barcodes, performs error-checking on them and send them in clear text through a normal character device file. NOTE : the company that created the CueCat has disappeared. CueCat readers are no longer produced or distributed.
at89prog is a command line serial and parallel port programmer for the Atmel AT89* series microcontrollers. Single bytes or complete files can be read and written. Both the code and the data memory can be accessed. Support is also available for erasing the code and data memory, resetting the device, and locking the memory.