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Application Design
Low-level Access to Peripherals
PDD header files are located in {InstallDir}\Processor Expert\lib\{MCU}\pdd. Each file
contains a definitions of PDD methods for one microcontroller peripheral. Basic PDD
methods are implemented by macros and do not provide any additional functionality like
register masking, shifting, etc.
Peripheral Base Address
PDD method parameters start with the base address of the peripheral. If user is writing a
code which is using a peripheral initialized by the existing component, it is recommend to
use the value {component_name}_DEVICE which gets replaced by the appropriate
address of the selected peripheral for the component. This is automatically done when you
drag and drop the PDD method from the PDD sub-folder of the Peripheral Initialization
component.
Figure 3.30 Peripheral Base Address
Otherwise, the peripheral base addresses can be found in the IO_Map.h file.
Processor Expert System Library
NOTE
PESL is supported only for 56800/E
PESL (Processor Expert System Library) is dedicated to power programmers, who are
familiar with the microcontroller architecture - each bit and each register. PESL provides
macros to access the peripherals directly. It should be used only in special cases when the
low-level approach is necessary.
PESL is peripheral oriented and complements with Embedded Components, which are
functionality oriented. While Embedded Components provide very high level of project
portability by stable API and inheritance feature across different CPU/DSP/PPC
architectures, PESL is more architecture dependent.
PESL commands grouped by the related peripheral can be found in Processor Expert
Components view in PESL folder.
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