07-02-2013, 04:24 PM
PIC 8 BIT AND 16 BIT MICROCONTROLLER ARCHITECTURE
PIC 8 BIT AND 16 BIT.pptx (Size: 530.76 KB / Downloads: 42)
The architectures of various PIC microcontrollers can be divided as follows :
Low - end PIC Architectures
Mid-range PIC Architectures
CPU Architecture
FSR Register(file selection register,address=04H,84H)-FSR is an 8 bit register used as data memory address pointer. This is used in indirect addressing mode
INDF Register(INDirect through FSR,address=00H,80H)-INDF is not a physical register. Accessing INDF access is the location pointed to by FSR in indirect addressing mode
PIC 8 bit and 16 bit architecture features:
Harvard architecture.
Small number of fixed length instruction.
A hardware stack for storing return address.
Data spaced mapped CPU , port and periferal registers.
Limitations
Only one accumulator
Operations and registers are not orthogonal
Register bank switching is required
Software implemented stacks are not efficient
Conclusion
Thus PIC architecture offers-
Seamless migration
Pin compatibility
Code compatibility
Again it gives-
Flexibility
Maximise reuse for future developments