LAPIS Semiconductor ML610471, User Manual, Page: 189 / 281

ML610471/472/473/Q471/Q472/Q473 User's Manual
Chapter 15 Port 4
15-1
15. Port 4
15.1 Overview
This LSI includes Port 4 (P42 to P47) which is an 6-bit input/output port.
This Port 4 can have the UART and RC-ADC output functions as the secondary and tertiary functions.
For the UART, see Chapter 11, "UART." For the RC-ADC, see Chapter 17, "RC Oscillation Type A/D Converter."
15.1.1 Features
•
Allows selection of high-impedance output, P-channel open drain output, N-channel open drain output, or CMOS
output for each bit in output mode.
•
Allows selection of high-impedance input, input with a pull-down resistor, or input with a pull-up resistor for each
bit in input mode.
•
The P44 pin can be used as the external clock input pin for the Timer 0 and Timer 2. The P45 pin can be used as
the external clock input pin for the Timer 1 and Timer 3.
•
The UART pins (RXD0, TXD0) and RC-ADC (channel 1) oscillation pins (IN1, CS1, RS1, RT1) can be used as
the secondary functions.
15.1.2 Configuration
Figure 15-1 shows the configuration of Port 4.
P4D : Port 4 data register
P4DIR : Port 4 direction register
P4CON0 : Port 4 control register 0
P4CON1 : Port 4 control register 1
P4MOD0 : Port 4 mode register 0
P4MOD1 : Port 4 mode register 1
Figure 15-1 Configuration of Port 4
Data bus
Output for UART (TXD0)
Output for RC-ADC (CS1, RS1, RT1)
P42 to P47
P4DIR
P4MOD0,1
P4CON0,1
V
DD
V
DD
V
SS
V
SS
6
4
Port4
Output
Controller
P4D
V
DD
V
SS
Pull-up
Pull-down
Controller
Input/Output for UART (RXD0)
Input for RC-ADC (IN1)
Input for timer
(T2CK, T3CK)
4
6