
6
AT89C51ID2
4289C–8051–11/05
Table 5. Port SFRs
Mnemonic
Add
Name
765432
10
P0
80h
8-bit Port 0
P1
90h
8-bit Port 1
P2
A0h
8-bit Port 2
P3
B0h
8-bit Port 3
P4
C0h
8-bit Port 4
P5
E8h
8-bit Port 5
----
P5
C7h
8-bit Port 5 (byte addressable)
Table 6. Flash and EEPROM Data Memory SFR
Mnemonic
Add
Name
765432
10
FCON
D1h
Flash Control
FPL3
FPL2
FPL1
FPL0
FPS
FMOD1
FMOD0
FBUSY
EECON
EEPROM data Control
Table 7. Timer SFRs
Mnemonic
Add
Name
765432
10
TCON
88h
Timer/Counter 0 and 1 Control
TF1
TR1
TF0
TR0
IE1
IT1
IE0
IT0
TMOD
89h
Timer/Counter 0 and 1 Modes
GATE1
C/T1#
M11
M01
GATE0
C/T0#
M10
M00
TL0
8Ah
Timer/Counter 0 Low Byte
TH0
8Ch
Timer/Counter 0 High Byte
TL1
8Bh
Timer/Counter 1 Low Byte
TH1
8Dh
Timer/Counter 1 High Byte
WDTRST
A6h
WatchDog Timer Reset
WDTPRG
A7h
WatchDog Timer Program
----
-
WTO2
WTO1
WTO0
T2CON
C8h
Timer/Counter 2 control
TF2
EXF2
RCLK
TCLK
EXEN2
TR2
C/T2#
CP/RL2#
T2MOD
C9h
Timer/Counter 2 Mode
----
--
T2OE
DCEN
RCAP2H
CBh
Timer/Counter 2 Reload/Capture
High byte
RCAP2L
CAh
Timer/Counter 2 Reload/Capture
Low byte
TH2
CDh
Timer/Counter 2 High Byte
TL2
CCh
Timer/Counter 2 Low Byte