AT89S51-24 ATMEL [ATMEL Corporation], AT89S51-24 Datasheet - Page 6

• Manufacturer Part Number: AT89S51-24
• Description: 8-bit Microcontroller with 4K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Special
Function
Registers
Table 1. AT89S51 SFR Map and Reset Values
6
0D8H
0D0H
0C8H
0C0H
0E8H
0E0H
0B8H
0B0H
0A8H
0A0H
0F8H
0F0H
98H
90H
88H
80H
XX000000
0X000000
00000000
00000000
00000000
11111111
11111111
00000000
11111111
00000000
11111111
SCON
TCON
PSW
ACC
P3
P2
P1
P0
IP
IE
B
AT89S51
XXXXXXXX
00000000
00000111
TMOD
SBUF
SP
A map of the on-chip memory area called the Special Function Register (SFR) space is shown
in Table 1.
Note that not all of the addresses are occupied, and unoccupied addresses may not be imple-
mented on the chip. Read accesses to these addresses will in general return random data,
and write accesses will have an indeterminate effect.
XXXXXXX0
00000000
00000000
AUXR1
DP0L
TL0
00000000
00000000
DP0H
TL1
00000000
00000000
DP1L
TH0
00000000
00000000
DP1H
TH1
XXXXXXXX
XXX00XX0
WDTRST
AUXR
0XXX0000
PCON
2487A–10/01
0FFH
0F7H
0EFH
0E7H
0DFH
0D7H
0CFH
0C7H
0BFH
0B7H
0AFH
0A7H
9FH
97H
8FH
87H