9.1 Program Memory Organization
PIC18 microcontrollers implement a 21-bit Program Counter, which is
capable of addressing a 2 Mbyte program memory space. Accessing a location between the
upper boundary of the physically implemented memory and the 2 Mbyte address will return all
‘0
’s (a NOP
instruction).
Refer to the following tables for device memory maps and code protection Configuration bits associated with the various sections of PFM.
The Reset vector address is at 000000h
. The PIC18-Q24 devices feature a vectored interrupt controller
with a dedicated interrupt vector table stored in the program memory. Refer to the “VIC
- Vectored Interrupt Controller Module” chapter for more details.