UM10310_1
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 01 — 1 December 2008
20 of 139
NXP Semiconductors
UM10310
P89LPC9321 User manual
1.6 Memory organization
The various P89LPC9321 memory spaces are as follows:
DATA —
128 bytes of internal data memory space (00h:7Fh) accessed via direct or
indirect addressing, using instruction other than MOVX and MOVC. All or part of the Stack
may be in this area.
IDATA —
Indirect Data. 256 bytes of internal data memory space (00h:FFh) accessed via
indirect addressing using instructions other than MOVX and MOVC. All or part of the
Stack may be in this area. This area includes the DATA area and the 128 bytes
immediately above it.
SFR —
Special Function Registers. Selected CPU registers and peripheral control and
status registers, accessible only via direct addressing.
XDATA —
‘External’ Data or Auxiliary RAM. Duplicates the classic 80C51 64 kB memory
space addressed via the MOVX instruction using the DPTR, R0, or R1. All or part of this
space could be implemented on-chip. The P89LPC9321 has 512 bytes of on-chip XDATA
memory, plus extended SFRs located in XDATA.
CODE —
64 kB of Code memory space, accessed as part of program execution and via
the MOVC instruction. The P89LPC9321 has 8 kB of on-chip Code memory.
The P89LPC9321 also has 512 bytes of on-chip Data EEPROM that is accessed via
SFRs (see Section
Fig 6.
P89LPC9321 memory map
002aae090
0000h
03FFh
0400h
07FFh
0800h
0BFFh
0C00h
0FFFh
SECTOR 0
SECTOR 1
SECTOR 2
SECTOR 3
1000h
13FFh
1400h
17FFh
1800h
1BFFh
1C00h
1E00h
1FFFh
SECTOR 4
SECTOR 5
SECTOR 6
FFEFh
FF00h
IAP entry-
points
SECTOR 7
ISP CODE
(512B)
(1)
SPECIAL FUNCTION
REGISTERS
(DIRECTLY ADDRESSABLE)
128 BYTES ON-CHIP
DATA MEMORY (STACK,
DIRECT AND INDIR. ADDR.)
4 REG. BANKS R[7:0]
data memory
(DATA, IDATA)
data EEPROM
DATA
128 BYTES ON-CHIP
DATA MEMORY (STACK
AND INDIR. ADDR.)
IDATA
(incl. DATA)
FFEFh
FFh
80h
7Fh
00h
FF1Fh
FF00h
entry points for:
-51 ASM. code
-C code
IDATA routines
1FFFh
1E00h
entry points for:
-UART (auto-baud)
-I2C, SPI, etc.
(1)
ISP serial loader
entry
points
read-protected
IAP calls only
DATA EEPROM
(512 BYTES)
[SFR ACCESS]
01FFh
0000h
EXTENDED SFRs
FFFFh
FFB0h
RESERVED
01FFh
XDATA
(512 BYTES)
0000h