Philips Semiconductors
Preliminary specification
80C51 8-bit Flash microcontroller family
16KB/32KB/64KB ISP/IAP Flash with 512B/512B/1KB RAM
89C51RB2/89C51RC2/
89C51RD2
Table 1. Special Function Registers
DIRECT
ADDRESS
BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION
RESET
VALUE
SYMBOL
DESCRIPTION
MSB
E7
–
LSB
E0
ACC*
AUXR#
AUXR1#
B*
Accumulator
E0H
8EH
A2H
F0H
E6
–
E5
E4
–
E3
–
E2
–
E1
00H
EXTRAM
Auxiliary
–
AO
xxxxxx10B
xxxxxxx0B
00H
ENBOOT
Auxiliary 1
B register
–
–
–
GF2
F3
0
–
DPS
F0
F7
F6
F5
F4
F2
F1
CCAP0H# Module 0 Capture High
CCAP1H# Module 1 Capture High
CCAP2H# Module 2 Capture High
CCAP3H# Module 3 Capture High
CCAP4H# Module 4 Capture High
CCAP0L# Module 0 Capture Low
CCAP1L# Module 1 Capture Low
CCAP2L# Module 2 Capture Low
CCAP3L# Module 3 Capture Low
CCAP4L# Module 4 Capture Low
FAH
FBH
FCH
FDH
FEH
EAH
EBH
ECH
EDH
EEH
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
xxxxxxxxB
CCAPM0# Module 0 Mode
CCAPM1# Module 1 Mode
CCAPM2# Module 2 Mode
CCAPM3# Module 3 Mode
CCAPM4# Module 4 Mode
DAH
DBH
DCH
DDH
DEH
–
–
–
–
–
ECOM CAPP
ECOM CAPP
ECOM CAPP
ECOM CAPP
ECOM CAPP
CAPN
CAPN
CAPN
CAPN
CAPN
MAT
MAT
MAT
MAT
MAT
TOG
TOG
TOG
TOG
TOG
PWM
PWM
PWM
PWM
PWM
ECCF
ECCF
ECCF
ECCF
ECCF
x0000000B
x0000000B
x0000000B
x0000000B
x0000000B
DF
CF
DE
CR
DD
–
DC
DB
DA
D9
D8
CCON*#
CH#
CL#
PCA Counter Control
PCA Counter High
PCA Counter Low
D8H
F9H
E9H
CCF4
CCF3
CCF2
CCF1
CCF0
00x00000B
00H
00H
CMOD#
PCA Counter Mode
D9H
CIDL
WDTE
–
–
–
CPS1
CPS0
ECF
00xxx000B
DPTR:
DPH
DPL
Data Pointer (2 bytes)
Data Pointer High
Data Pointer Low
83H
82H
00H
00H
AF
EA
BF
–
AE
EC
AD
ET2
BD
AC
ES
AB
ET1
BB
AA
EX1
BA
A9
ET0
B9
A8
EX0
B8
IE*
Interrupt Enable 0
Interrupt Priority
A8H
B8H
B7H
00H
BE
BC
PS
IP*
PPC
B6
PT2
B5
PT1
B3
PX1
B2
PT0
B1
PX0
B0
x0000000B
x0000000B
B7
–
B4
IPH#
Interrupt Priority High
PPCH
PT2H
PSH
PT1H
PX1H
PT0H
PX0H
87
AD7
97
86
AD6
96
85
AD5
95
84
AD4
94
83
AD3
93
82
AD2
92
81
AD1
91
80
AD0
90
P0*
P1*
P2*
P3*
Port 0
Port 1
Port 2
80H
90H
A0H
FFH
FFH
FFH
CEX4
A7
CEX3
A6
CEX2
A5
CEX1
A4
CEX0
A3
ECI
A2
T2EX
A1
T2
A0
AD15
B7
AD14
B6
AD13
B5
AD12
B4
AD11
B3
AD10
B2
AD9
B1
AD8
B0
Port 3
B0H
87H
RD
WR
T1
T0
INT1
INT0
TxD
RxD
FFH
1
PCON#
Power Control
SMOD1 SMOD0
–
–
GF1
GF0
PD
IDL
00xxx000B
*
SFRs are bit addressable.
#
–
SFRs are modified from or added to the 80C51 SFRs.
Reserved bits.
1. Reset value depends on reset source.
8
1999 Sep 23