Finding the Address Range of Virtually Mapped Special Function Registers in PIC18F452 Microcontroller
What is the address range of the virtually mapped special function registers (SFRs) within the Access Bank of the PIC18F452 microcontroller?
a. None of these answers
b. 0x80 to 0xFF
c. 0x00 to 0x80
d. 0x00 to 0xFF
Final answer:
Answer:
The address range of virtually mapped special function registers (SFRs) within the Access Bank of the PIC18F452 microcontroller is from 0xF80 to 0xFFF, making use of mirrored addresses in the ranges 0x00 to 0x7F and 0x80 to 0xFF. Therefore the correct answer is d. 0x00 to 0xFF.
Explanation:
The special function registers (SFRs) of the PIC18F452 microcontroller are allocated in a specific area of memory known as the Access Bank. This arrangement allows for more efficient access to the SFRs without the need to change the bank bits in the STATUS register.
The address range for these virtually mapped SFRs within the Access Bank starts at address 0xF80 and ends at address 0xFFF. This means that options 'b. 0x80 to 0xFF' and 'c. 0x00 to 0x80' are incorrect. Option 'a. None of these answers' is also incorrect as there is a specific address range allocated for the SFRs.
Therefore, the correct answer for the range of SFRs in the Access Bank is 'd. 0x00 to 0xFF', taking into account the mirrored addresses in the range of 0x00 to 0x7F and 0x80 to 0xFF, which repeat every 256 bytes up through the range 0xF00 to 0xFFF.