User`s guide

General xPC Target™ Troubleshooting
availablespaceonthedisk.Thesignaldata will m ost likely be corrupted and
irretrievable. You should delete the signal data file and reboot the xPC Target
system. To prevent this occurrence, monitor the size of the s ignal data file
as the scope acquires data.
Refer to the MathWorks Support xPC Target Web site
(
http://www.mathworks.com/support/product/XP) for additional
information.
Can I Write Custom xPC Target Device Drivers?
You might wan t to write your own driver if you want to include an
unsupported device driver in your xPC Target system . See the xPC Target
Device Drivers Guide for details.
Before you consider writing custom device drivers for the xPC Targe t system,
you should posses s
• Good C programming skills
• Knowledge of writing S-functions and compiling those functions as C-MEX
functions
• Knowledge of SimStruct, a MAT LAB Simulin k C lang uage header file that
defines the Simulink data structure and the SimStruct access macros. It
encapsulates all the data relating to the m odel or S-function, including
block parame ters and outputs.
• An excellent understanding of the I/O hardware. Because of the real-time
nature of the xPC Target system, you must develop drivers with minimal
latency. And since most drivers access the I/O hardware at the low est
possible level (register programmin g) , you must have a good understandin g
of how to control the board with register information. Indirectly, this
means that you must have access to the register-le vel programm i ng
manual for the device.
• A good kno wledge of port and memory I/O a ccess ov er vario us buses. You
need this information to a ccess I/O hardware at the register level.
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