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ABOV Semiconductor Co., Ltd.
9.5 P2 Port
9.5.1 P2 Port Description
P2 is 8-bit I/O port. P2 control registers consist of P2 data register (P2), P2 direction register (P2IO), P2 pull-up resistor
selection register (P2PU) andP2 open-drain selection register (P2OD).Refer to the port function selection registers for
the P2 function selection.
9.5.2 Register description for P2
P2 (P2 Data Register): 90H
Initial value: 00H
NOTE)
1. Do not use the “direct bit test and branch” instruction for input port. More detail information is at chapter
17.2 Instructions on how to use the input port.
Example) Avoid direct input port bit test and branch condition as below
if(P20) → if(P2 & 0x01)
P2IO (P2 Direction Register): B9H
Initial value: 00H
NOTE)
1. SS1 function possible when input