Programs containing PET specific code may use the
header files. Using the later may be an option when writing code for more than
one CBM platform, since it includes
pet.h and declares several functions
common to all CBM platforms.
There are currently no special PET functions.
Some functions are available for all (or at least most) of the Commodore machines. See the function reference for declaration and usage.
The following pseudo variables declared in the
pet.h header file do allow
access to hardware located in the address space. Some variables are
structures, accessing the struct fields will access the chip registers.
Access to the two PIA (peripheral interface adapter) chips is available via
PIA2 variables. The structure behind these variables
is explained in
VIA structure allows access to the VIA (versatile interface
adapter). See the
_6522.h header file located in the include
directory for the declaration of the structure.