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CHAPTER 4 PIN FUNCTIONS (
μ
PD78018FY SUBSERIES)
4.2.6 P50-P57 (Port5)
These pins form an 8-bit I/O port, port 5, which also serves as an address bus.
These pins can directly drive LEDs.
Port 5 can be set in the following operation modes in 1-bit units.
(1) Port mode
In this mode, P50 through P57 constitute an 8-bit I/O port which can be set in the input or output mode in 1-
bit units by using the port mode register 5 (PM5). When used as an input port, an internal pull-up resistor
can be used if so specified by the pull-up resistor option register (PUO).
(2) Control mode
In this mode, P50 through P57 function as the high-order address bus pins (A8-A15) in the external memory
extension mode. The pins used as address bus pins are automatically disconnected from the internal pull-
up resistor.
4.2.7 P60-P67 (Port6)
These pins constitute an 8-bit I/O port, port 6, which can be also used to output control signals in the external
memory extension mode.
P60 through P63 can directly drive LEDs.
Port 6 can be set in the following operation modes in 1-bit units.
(1) Port mode
In this mode, P60 through P67 constitute an 8-bit I/O port, which can be set in the input or output mode in
1-bit units by using the port mode register 6 (PM6).
P60 through P63 are N-ch open drain pins. These pins of the mask ROM model can be connected to an internal
pull-up resistor by mask option.
When using P64 through P67 as input port pins, an internal pull-up resistor can be used if so specified by the
pull-up resistor option register (PUO).
(2) Control mode
In this mode, P60 through P67 functions as control signal output pins (RD, WR, WAIT, and ASTB) in the
from the internal pull-up resistor.
Caution If the external wait state is not used in the external memory extension mode, P66 can be used
as an I/O port pin.
4.2.8 AV
REF
This pin inputs a reference voltage to the A/D converter.
Connect this pin to V
SS
when the A/D converter is not used.
4.2.9 AV
DD
This is the analog power supply pin of the A/D converter.
Keep this pin at the same voltage as the V
DD
pin even when the A/D converter is not used.
4.2.10 AV
SS
This is the ground pin of the A/D converter.
Keep this pin at the same voltage as the V
SS
pin even when the A/D converter is not used.