PIC24FV32KA304 Datasheet, PDF (38/322 Pages) Microchip Technology – 20/28/44/48-Pin, General Purpose, 16-Bit Flash Microcontrollers with XLP Technology

PIC24FV32KA304 FAMILY
4.1.1
PROGRAM MEMORY
ORGANIZATION
The program memory space is organized in
word-addressable blocks. Although it is treated as
24 bits wide, it is more appropriate to think of each
address of the program memory as a lower and upper
word, with the upper byte of the upper word being
unimplemented. The lower word always has an even
address, while the upper word has an odd address, as
shown in Figure 4-2.
Program memory addresses are always word-aligned
on the lower word, and addresses are incremented or
decremented by two during code execution. This
arrangement also provides compatibility with data
memory space addressing and makes it possible to
access data in the program memory space.
4.1.2 HARD MEMORY VECTORS
All PIC24F devices reserve the addresses between
00000h and 000200h for hard coded program
execution vectors. A hardware Reset vector is provided
to redirect code execution from the default value of the
PC on device Reset to the actual start of code. A GOTO
instruction is programmed by the user at 000000h, with
the actual address for the start of code at 000002h.
PIC24F devices also have two interrupt vector
tables, located from 000004h to 0000FFh and
000104h to 0001FFh. These vector tables allow each
of the many device interrupt sources to be handled
by separate ISRs. A more detailed discussion of the
interrupt vector tables is provided in Section 8.1
“Interrupt Vector (IVT) Table”.
4.1.3 DATA EEPROM
In the PIC24FV32KA304 family, the data EEPROM is
mapped to the top of the user program memory space,
starting at address, 7FFE00, and expanding up to
address, 7FFFFF.
The data EEPROM is organized as 16-bit wide memory
and 256 words deep. This memory is accessed using
table read and write operations similar to the user code
memory.
4.1.4 DEVICE CONFIGURATION WORDS
Table 4-1 provides the addresses of the device
Configuration Words for the PIC24FV32KA304 family.
Their location in the memory map is shown in
Figure 4-1.
For more information on device Configuration Words,
see Section 26.0 “Special Features”.
TABLE 4-1:
DEVICE CONFIGURATION
WORDS FOR PIC24FV32KA304
FAMILY DEVICES
Configuration Words
Configuration Word
Addresses
FBS
FGS
FOSCSEL
FOSC
FWDT
FPOR
FICD
FDS
F80000
F80004
F80006
F80008
F8000A
F8000C
F8000E
F80010
FIGURE 4-2:
PROGRAM MEMORY ORGANIZATION
msw
Address
most significant word
least significant word
23
16
8
000001h
00000000
000003h
00000000
000005h
00000000
000007h
00000000
Program Memory
‘Phantom’ Byte
(read as ‘0’)
Instruction Width
PC Address
(lsw Address)
0
000000h
000002h
000004h
000006h
 2011 Microchip Technology Inc.
DS39995A-page 38