UPD62A NEC, UPD62A Datasheet - Page 16

• Manufacturer Part Number: UPD62A
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC

3.2 K
3.2.1 K
5 of the P4 register.
3.2.2 S
in 2-bit units by means of bit 4 of the P4 register.
from flowing internally. In OFF mode, “1” can be read regardless of the pin status.
3.2.3 S
input and output mode.
in 2-bit units by means of bit 4 of the P4 register.
transmission display pin (refer to 4. TIMER).
16
The K
The pin status can be read at this port.
Software can be used to set whether to connect a pull-down resistor at the K
When reset, a pull-down resistor is connected.
b
b
b
Caution In order to prevent malfunction, be sure to input a low level to more than one of pins K
The S
The pin status can be read by setting this port to input mode with bit 0 of the P4 register.
In input mode, software can be used to set whether to connect a pull-down resistor at the S
If input mode is canceled (set to OFF mode), the pin becomes high-impedance, but the through current is stopped
When reset, this port is set to OFF mode and becomes high-impedance.
The S
This port is set input or output mode by means of bit 2 of the P4 register. The pin status can be read in both
In input mode, software can be used to set whether to connect a pull-down resistor at the S
In output mode, the pull-down resistor is automatically disconnected, and this port becomes the remote control
When reset, this port is placed in output mode, and a high level is output.
2
3
4
:
:
to b
I
I
0
1
Port/Special Ports (P1)
I
0
1
/LED (bit 3 of P1)
port (P
7
/LED port is an input/output port.
port (bit 2 of P1)
port is a 4-bit input port for key entry.
:
port is the input/OFF mode port.
when reset is released (when the RESET pin changes from low level to high level, or POC is
released due to supply voltage startup).
In input mode, the status of the S
In OFF mode, this bit is fixed to 1.
The status of the S
The status of the K
Bit
Name
11
: bits 4 to 7 of P1)
b
K
7
I3
1
I
/LED pin is read regardless of input/output mode (Read only).
pin is read (Read only).
Table 3-3. K
b
K
6
I2
Data Sheet U14474EJ1V0DS00
0
b
K
I
5
I1
/Special Port Register (P1)
pin is read (Read only).
b
K
4
I0
b
S
3
1
/LED
b
S
2
0
I
port in 4-bit units by means of bit
b
(Fixed to 1)
1
b
0
0
0
and S
and S
1
1
/LED ports
/LED ports
I0
to K
PD62A
I3