Abov MC97F2664, Руководство пользователя

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MC97F2664
84 April 11, 2014 Ver. 1.4
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), 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
7 6 5 4 3 2 1 0
P47 P46 P45 P44 P43 P42 P41 P40
R/W R/W R/W R/W R/W R/W R/W R/W
Initial value : 00H
P4[7:0]
I/O Data
P4IO (P4 Direction Register) : C1H
7 6 5 4 3 2 1 0
P47IO P46IO P45IO P44IO P43IO P42IO P41IO P40IO
R/W R/W R/W R/W R/W R/W R/W R/W
Initial value : 00H
P4IO[7:0]
P4 Data I/O Direction
0 Input
1 Output
NOTE) SS1/RXD2/RXD3 function possible when input
P4PU (P4 Pull-up Resistor Selection Register) : 100CH (XSFR)
7 6 5 4 3 2 1 0
P47PU P46PU P45PU P44PU P43PU P42PU P41PU P40PU
R/W R/W R/W R/W R/W R/W R/W R/W
Initial value : 00H
P4PU[7:0]
Configure Pull-up Resistor of P4 Port
0 Disable
1 Enable
P4OD (P4 Open-drain Selection Register) : 1004H (XSFR)
7 6 5 4 3 2 1 0
P47OD P46OD P45OD P44OD P43OD P42OD P41OD P40OD
R/W R/W R/W R/W R/W R/W R/W R/W
Initial value : 00H
P4OD[7:0]
Configure Open-drain of P4 Port
0 Push-pull output