Oki ML63611, User Manual

Page: 111 / 271

ML63611 User’s Manual
Chapter 10 Ports (INPUT, I/O PORT)
10 – 3
OPTION B (D): 1.5 V (3.0 V), With regulator
circuit for LCD bias
OPTION A (C): 1.5 V (3.0 V), Without regulator
circuit for LCD bias
(2) Port 0 control registers 0/1 (P0CON0, P0CON1)
P0CON0 and P0CON1 are 4-bit special function registers (SFRs) that select pull-up or pull-down resistors
and select the external interrupt sampling frequency of Port 0 secondary function.
At system reset, all the input modes for the four bits of P0CON0 are set to the input mode set by the mask
option, and 128 Hz is selected as the external interrupt sampling frequency (however, all the bits enters the
interrupt disabled state).
bit 1: P0PUD
This bit is used to select pull-up or pull-down resistors when any of the port 0 pins are selected by
P0CON0 as an input with pull-up/pull-down resistor.
Setting P0PUD to “0” selects pull-down resistors, and setting to “1” selects pull-up resistors.
Individual specification of pull-down or pull-up resistors for the pins of port 0.0 to 0.3 is not
possible.
Note:
Use the mask option to specify the initial value at system reset of P0PUD.
P03MD P02MD P01MD P00MD
P0CON0 (010H)
(R/W)
bit 3 bit 2 bit 1 bit 0
Port 0.3 input mode select
0: Input with pull-up/pull-down resistor (initial value)
1: High impedance input
Port 0.2 input mode select
0: Input with pull-up/pull-down resistor (initial value)
1: High impedance input
Port 0.1 input mode select
0: Input with pull-up/pull-down resistor (initial value)
1: High impedance input
Port 0.0 input mode select
0: Input with pull-up/pull-down resistor (initial value)
1: High impedance input
 
P0PUD P0F
P0CON1 (011H)
(R/W)
bit 3 bit 2 bit 1 bit 0
Port 0 pull-up/pull-down resistor mode select
0: Inputs with pull-down resistors (initial value)
1: Inputs with pull-up resistors
External interrupt sampling frequency select
0: 128 Hz sampling (initial value)
1: 4 kHz sampling
!