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Rev. 1.00
118 of ���
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Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Input/Output Ports
Register Description
This section provides a description of all the registers associated with I/O setup and control. The
following table gives a summary of all associated I/O registers, which will be described in detail
later.
I/O Register List
Register
Name
Bit
7
6
5
4
3
2
1
0
P0WAKE
P07WU
P06WU
P0�WU
P04WU
P03WU
P0�WU
P01WU
P00WU
P0
P0.7
P0.6
P0.�
P0.4
P0.3
P0.�
P0.1
P0.0
P0M0
P0M0.7
P0M0.6
P0M0.�
P0M0.4
P0M0.3
P0M0.�
P0M0.1
P0M0.0
P0M1
P0M1.7
P0M1.6
P0M1.�
P0M1.4
P0M1.3
P0M1.�
P0M1.1
P0M1.0
P1
P1.7
P1.6
P1.�
P1.4
P1.3
P1.�
P1.1
P1.0
P1M0
P1M0.7
P1M0.6
P1M0.�
P1M0.4
P1M0.3
P1M0.�
P1M0.1
P1M0.0
P1M1
P1M1.7
P1M1.6
P1M1.�
P1M1.4
P1M1.3
P1M1.�
P1M1.1
P1M1.0
P�
P�.7
P�.6
P�.�
P�.4
P�.3
P�.�
P�.1
P�.0
P�M0
P�M0.7
P�M0.6
P�M0.�
P�M0.4
P�M0.3
P�M0.�
P�M0.1
P�M0.0
P�M1
P�M1.7
P�M1.6
P�M1.�
P�M1.4
P�M1.3
P�M1.�
P�M1.1
P�M1.0
P3
P3.7
P3.6
P3.�
P3.4
P3.3
P3.�
P3.1
P3.0
P3M0
P3M0.7
P3M0.6
P3M0.�
P3M0.4
P3M0.3
P3M0.�
P3M0.1
P3M0.0
P3M1
P3M1.7
P3M1.6
P3M1.�
P3M1.4
P3M1.3
P3M1.�
P3M1.1
P3M1.0
P4
P4.7
P4.6
P4.�
P4.4
P4.3
P4.�
P4.1
P4.0
P�
P�.7
P�.6
P�.�
P�.4
P�.3
P�.�
P�.1
P�.0
SRCR
—
—
SRCR.�
SRCR.4
SRCR.3
SRCR.�
SRCR.1
SRCR.0
Each Port has its own data register, known as P0, P1, P2, P3, P4 and P5 which are used to control
the input and output I/O pin data. These registers read input pin data or write output pin data on the
selected I/O pin. For I/O pins setup as outputs a read operation to these registers will setup either
a high or low level on the corresponding pin. For I/O pins setup as inputs a read operation to these
registers will read the actual logic level on the corresponding pin.
P0 Register
SFR Address: 80h
Bit
7
6
5
4
3
2
1
0
Name
P0.7
P0.6
P0.�
P0.4
P0.3
P0.�
P0.1
P0.0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
P1 Register
SFR Address: 90h
Bit
7
6
5
4
3
2
1
0
Name
P1.7
P1.6
P1.�
P1.4
P1.3
P1.�
P1.1
P1.0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1