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Rev.1.04
Aug 23, 2007
REJ03B0188-0104
4559 Group
PIN DESCRIPTION
Table 3
Pin description
Pin
Name
Input/Output
Function
VDD
Power source
Connected to a plus power supply.
VSS
Power source
Connected to a 0 V power supply.
CNVSS
This pin is shared with the VPP pin which is the power source input pin for
programming the built-in QzROM. Connect to VSS through a resistor about 5 k
.
VDCE
Voltage drop
detection circuit
enable
Input
This pin is used to operate/stop the voltage drop detection circuit.
When “H“ level is input to this pin, the circuit starts operating.
When “L“ level is input to this pin, the circuit stops operating.
XIN
Main clock input
Input
I/O pins of the main clock generating circuit. When using a ceramic resonator,
connect it between pins XIN and XOUT. A feedback resistor is built-in between them.
When using the RC oscillation, connect a resistor and a capacitor to XIN, and leave
XOUT pin open.
XOUT
Main clock output
Output
XCIN
Sub clock input
Input
I/O pins of the sub-clock generating circuit. Connect a 32.768 kHz quartz-crystal
oscillator between pins XCIN and XCOUT. A feedback resistor is built-in between them.
XCIN and XCOUT pins are also used as ports D6 and D7, respectively.
XCOUT
Sub clock output
Output
RESET
Reset I/O
I/O
An N-channel open-drain I/O pin for a system reset. When the SRST instruction,
watchdog timer, the built-in power-on reset or the voltage drop detection circuit
causes the system to be reset, the RESET pin outputs “L” level.
D0
D5
I/O port D
(Input is examined
by skip decision.)
I/O
Each pin of port D has an independent 1-bit wide I/O function. The output structure
can be switched to N-channel open-drain or CMOS by software. For input use, set
the latch of the specified bit to “1” and select the N-channel open-drain.
Port D5 is also used as INT pin.
D6, D7
Output port D
Output
Each pin of port D has an independent 1-bit wide output function. The output
structure is N-channel open-drain.
Ports D6 and D7 are also used as XCIN pin and XCOUT pin, respectively.
P00
P03
I/O port P0
I/O
Port P0 serves as a 4-bit I/O port. The output structure can be switched to N-channel
open-drain or CMOS by software. For input use, set the latch of the specified bit to
“1” and select the N-channel open-drain. Port P0 has a key-on wakeup function and
a pull-up function. Both functions can be switched by software.
Ports P00–P03 are also used as SEG16–SEG19, respectively.
P10
P13
I/O port P1
I/O
Port P1 serves as a 4-bit I/O port. The output structure can be switched to N-channel
open-drain or CMOS by software. For input use, set the latch of the specified bit to
“1” and select the N-channel open-drain. Port P1 has a key-on wakeup function and
a pull-up function. Both functions can be switched by software.
Ports P10–P13 are also used as SEG20–SEG23, respectively.
P20
P23
I/O port P2
I/O
Port P2 serves as a 4-bit I/O port. The output structure can be switched to N-channel
open-drain or CMOS by software. For input use, set the latch of the specified bit to
“1” and select the N-channel open-drain. Port P2 has a key-on wakeup function and
a pull-up function. Both functions can be switched by software.
Ports P20–P23 are also used as SEG24–SEG27, respectively.
P30
P33
I/O port P3
I/O
Port P3 serves as a 4-bit I/O port. The output structure can be switched to N-channel
open-drain or CMOS by software. For input use, set the latch of the specified bit to
“1” and select the N-channel open-drain. Port P3 has a key-on wakeup function and
a pull-up function. Both functions can be switched by software.
Ports P30–P33 are also used as SEG28–SEG31, respectively.
C
Output port C
Output
1-bit output port. The output structure is CMOS. Port C is also used as CNTR pin.
COM0
COM3 Common output
Output
LCD common output pins. Pins COM0 and COM1 are used at 1/2 duty, pins COM0–
COM2 are used at 1/3 duty and pins COM0–COM3 are used at 1/4 duty.
SEG0
SEG31 Segment output
Output
LCD segment output pins.
SEG0–SEG2 pins are used as VLC3–VLC1 pins, respectively.
SEG16–SEG31 pins are used as Ports P00–P03, Ports P10–P13, Ports P20–P23, and
Ports P30–P33, respectively.
CNTR
Timer I/O
I/O
CNTR pin has the function to input the clock for the timer 1 event counter and to
output the PWM signal generated by timer 2. CNTR pin is also used as Port C.
INT
Interrupt input
Input
INT pin accepts external interrupts. They have the key-on wakeup function which
can be switched by software. INT pin is also used as Port D5.
VLC3
VLC1
LCD power source
These are the LCD power supply pins. If an internal resistor is used, connect the
VLC3 pin to the VDD pin. (If brightness adjustment is required, connect via a resistor.)
When using an external power supply, apply voltage such that VSS
≤ VLC1 ≤ VLC2 ≤
VLC3
≤ VDD. Pins VLC3 to VLC1 also function as pins SEG0 to SEG2.