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ABOV Semiconductor Co., Ltd.
9.7 P4 Port
9.7.1 P4 Port Description
P4 is 8-bit I/O port. P4 control registers consist of P4 data register (P4), P4 direction register (P4IO), debounce enable
register (P46DB), P4 pull-up resistor selection register (P4PU) and P4 open-drain selection register (P4OD).Refer to
the port function selection registers for the P4 function selection.
9.7.2 Register description for P4
P4 (P4 Data Register): A0H
Initial value: 00H
P4IO (P4 Direction Register): B1H
Initial value: 00H
NOTE)
1. EINT10–EINT12/EC0–EC2/SS0 function possible
when input
P4PU (P4 Pull-up Resistor Selection Register): EEH
Initial value: 00H
Configure Pull-up Resistor of P4 Port
P4OD (P4 Open-drain Selection Register): 4014H (XSFR)
Initial value: 00H
Configure Open-drain of P4 Port