P50 To P53 (Port 5); P60 To P63 (Port 6); Reset; X1, X2 ( Μ Pd789104, 789114 Subseries) - NEC mPD789101 User Manual

(h) RxD20, TxD20
These are the serial data I/O pins of the asynchronous serial interface.
(i) ASCK20
This is the serial clock input pin of the asynchronous serial interface.
Caution When using these pins as serial interface pins, the input/output mode and output latch must be
set according to the functions to be used. For the details of the setting, refer to Table 13-2 Serial
Interface 20 Operating Mode Settings.

3.2.4 P50 to P53 (Port 5)

This is a 4-bit N-ch open-drain I/O port. Port 5 can be specified in input or output mode in 1-bit units by using
port mode register 5 (TM5). For a mask ROM version, use of an on-chip pull-up resistor can be specified by the mask
option.

3.2.5 P60 to P63 (Port 6)

This is a 4-bit input-only port. In addition to general-purpose input ports, these pins function as the A/D converter
input pins.
(1) Port mode
In the port mode, port 6 functions as a 4-bit input-only port.
(2) Control mode
In the control mode, the pins of port 6 can be used as A/D converter analog inputs (ANI0 to ANI3).

3.2.6 RESET

This pin inputs an active-low system reset signal.
3.2.7 X1, X2 ( µ PD789104, 789114 Subseries)
These pins are used to connect a crystal resonator for system clock oscillation.
To supply an external clock, input the clock to X1 and input the inverted signal to X2.
3.2.8 CL1, CL2 ( µ PD789124, 789134 Subseries)
Resistor (R) and capacitor (C) connect pins for system clock oscillation.
3.2.9 AV
DD
Analog power supply pin of the A/D converter. Always use the same potential as that of the V
the A/D converter is not used.
3.2.10 AV
SS
This is a ground potential pin of the A/D converter. Always use the same potential as that of the V
when the A/D converter is not used.
3.2.11 V
DD
Positive power supply pin
3.2.12 V
SS
Ground pin
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CHAPTER 3 PIN FUNCTIONS
User's Manual U13045EJ2V0UM00
pin even when
DD
pin even
SS