The PC/104 computer is a stack of small 3.5" square cards connected by an ISA communication bus. There are two cards in this stack: The Advantech CPU card and the Sensoray 526 DAQ card. The Advantech card has the processor and all of the connectors to various peripherals on it (keyboard, Ethernet, VGA). The Sensoray card has Digital\Analog In\Outs.
xPC is a real-time operating system based on the Matlab\Simulink environment. Programs are created through simple drag-and-drop procedures and requires very little "coding." Simulink models are compiled on a Host PC into C programs that run on a Target PC. "Real-time" means that code is executed at very regular intervals, very useful for control.
Out of the box, the Advantech CPU card has to be configured. This involves connecting various peripherals and editing the BIOS settings. Additionally, because we use a CompactFlash disk in place of a hard drive, this card needs to be configured as a bootable disk. We will format the disk so that it will automatically boot into xPC when the board is powered.
Using xPC involves compiling and downloading a Simulink model onto the Target PC. You create a model in Simulink, adjust various configuration parameters, and then build the program. The program is then automatically downloaded to the Target PC. It can then be triggered to run externally using the Simulink External mode on the Host PC or through commands in an M-file script.