PD17225_15 Datasheet, PDF (27/86 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLER FOR SMALL GENERAL-PURPOSE INFRARED REMOTE CONTROL TRANSMITTER

µPD17225, 17226, 17227, 17228
3. PORTS
3.1 Port 0A (P0A0-P0A3)
This is a 4-bit input port. Data is read through port register P0A (address 70H). This port is a CMOS input port with
a pull-up resistor, and can be used for key return input for a key matrix.
When a low-level signal is input to at least one of the pins in this port in the standby mode, the standby mode is released.
3.2 Port 0B (P0B0-P0B3)
This is a 4-bit input port. Data is read through port register P0B (address 71H). This port is a CMOS input port with
a pull-up resistor, and can be used for key return input for a key matrix.
When a low-level signal is input to at least one of the pins in this port in the standby mode, the standby mode is released.
3.3 Port 0C (P0C0-P0C3)
This is a 4-bit output port. The contents of the output latch are read and output data is set through port register P0C
(address 72H). This port is an N-ch open-drain output port, and can be used as the key source of a key matrix.
In the standby mode, this port outputs low-level signals.
3.4 Port 0D (P0D0-P0D3)
This is a 4-bit output port. The contents of the output latch are read and output data is set through port register P0D
(address 73H). This port is an N-ch open-drain output port, and can be used as the key source for a key matrix.
In the standby mode, this port outputs low-level signals.
3.5 Port 0E (P0E0-P0E3)
This is a 4-bit I/O port which can be set in either the input or output mode in 1-bit units by the P0EBIO (address 27H)
of the register file.
To read the input data or to set the output data, use the P0E register (address 6F). When data is read in the output
mode, the contents of the output latch are read.
Connection of a pull-up resistor can be specified in 1-bit units by the P0EBPU (address 17H) of the register file. (When
the pull-up resistor is connected, note that the pull-up resistor is not disconnected even when the output mode is set.)
On reset, this port functions as an input port.
Data Sheet U12643EJ2V0DS00
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