Tiny module delivers Pico-ITXe expansion
By Warren Webb, Technical Editor -- EDN, November 11, 2008
As standard off-the-shelf board architectures shrink, designers need simple and low-cost techniques to tack on custom I/O. Toward that end, WinSystems recently introduced the first Pico-I/O module for expanding Pico-ITXe single-board computers. The 48-point PCO-UIO48-G digital-I/O interface has an interruptible event sensor. The card monitors 24 of the rising and falling digital-edge transitions, latches them, and then signals the host processor that a change of input status has occurred. This approach is the most efficient way of sensing and signaling a CPU of real-time events without the burden of continuous polling of the digital-I/O points.
WinSystems based the PCO-UIO48-G’s I/O controller on a Lattice FPGA programmed to support various I/O and interrupt configurations. Each I/O line is programmable for input, output, or output with read-back operation. Each line’s transition is latched, so that the module recognizes even short pulses. A Pico-I/O module measures 60×72 mm, which is approximately half the area of a PC/104 module. The Pico-I/O employs the SUMIT (stackable-unified-module-interconnect-technology) connector, which the SFF-SIG (Small Form Factor Special Interest Group) developed. The PCO-UIO48-G has a list price of $59 and is available from stock to two weeks.
