Low-level access to peripherals

In some cases, a non-standard use of the peripheral is required and it is more efficient to write a custom peripheral driver from scratch than to use the component. In addition, there are special features present only on a particular chip derivative (not supported by the component) that could make the user routines more effective; however, the portability of such code is reduced.

• Peripheral initialization
  
• Peripheral driver implementation
  
• Physical device drivers
  
• Processor Expert system library
  
• Direct access to peripheral registers