PIC18FXX39 Datasheet, PDF (33/322 Pages) Microchip Technology – Enhanced FLASH Microcontrollers with Single Phase Induction Motor Control Kernel

PIC18FXX39
4.0 MEMORY ORGANIZATION
There are three memory blocks in Enhanced MCU
devices. These memory blocks are:
• Program Memory
• Data RAM
• Data EEPROM
Data and program memory use separate busses,
which allows for concurrent access of these blocks.
Additional detailed information for FLASH program
memory and Data EEPROM is provided in Section 5.0
and Section 6.0, respectively.
4.1 Program Memory Organization
A 21-bit program counter is capable of addressing the
2-Mbyte program memory space. Accessing a location
between the physically implemented memory and the
top of the 2-MByte range will cause a read of all ‘0’s (a
NOP instruction).
The PIC18F2539 and PIC18F4539 each have a total of
24 Kbytes, or 12K of single word instructions of FLASH
memory, from addresses 0000h to 5FFFh. The next
8 Kbytes beyond this space (from 6000h to 7FFFh) are
reserved for the Motor Control kernel; accessing
locations in this range will return random information.
The PIC18F2439 and PIC18F4439 each have
12 Kbytes, or 6K of single word instructions of FLASH
memory, from addresses 0000h to 2FFFh. The next
4 Kbytes of this space (from 3000h to 3FFFh) are
reserved for the Motor Control kernel; accessing
locations in this range will return random information.
The RESET vector address for all devices is at 0000h,
and the interrupt vector addresses are at 0008h and
0018h.
The memory maps for the PIC18FX439 and
PIC18FX539 devices are shown in Figure 4-1.
Note:
The ProMPT Motor Control kernel is iden-
tical for all PIC18FXX39 devices, regard-
less of the difference in reserved block size
between PIC18FX439 and PIC18FX539
devices
FIGURE 4-1:
PROGRAM MEMORY MAP AND STACK FOR PIC18FXX39 DEVICES
PC<20:0>
CALL,RCALL,RETURN
21
RETFIE,RETLW
PIC18FX439 Devices
Stack Level 1



Stack Level 31
PIC18FX539 Devices
RESET Vector
0000h
RESET Vector
0000h
High Priority Interrupt Vector 0008h
High Priority Interrupt Vector 0008h
Low Priority Interrupt Vector 0018h
Low Priority Interrupt Vector 0018h
On-Chip
Program Memory
Reserved
2FFFh
3000h
3FFFh
4000h
On-Chip
Program Memory
Read '0'
Reserved
5FFFh
6000h
7FFFh
8000h
Note:
1FFFFFh
200000h
Size of memory areas not to scale.
Read '0'
1FFFFFh
200000h
 2002-2013 Microchip Technology Inc.
Preliminary
DS30485B-page 33