CHAPTER 2 PIN FUNCTIONS
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User’s Manual U14359EJ4V0UM
(15) PDL0 to PDL15 (Port DL) ··· 3-state I/O
PDL0 to PDL15 function as an 8- or 16-bit I/O port that can be set to input or output in 1-bit units.
Besides functioning as a port, in control mode (external expansion mode), these pins operate as a data bus
(D0 to D15) for when the memory is expanded externally.
The operation mode can be set to port or control mode in 1-bit units, specified by the port DL mode control
register (PMCDL).
(a) Port mode
PDL0 to PDL15 can be set to input or output in 1-bit units using the port DL mode register (PMDL).
(b) Control mode
PDL0 to PDL15 can be set to function alternately as D0 to D15 using the PMCDL register.
(i)
D0 to D15 (Data) ··· 3-state I/O
These pins constitute a data bus for when the external memory is accessed. These are 16-bit data
I/O bus pins.
The output changes in synchronization with the rise of the CLKOUT signal in the T1 state. In the
idle state (TI), these pins become high impedance.
(16) CKSEL (Clock generator operating mode select) ··· input
This is an input pin used to specify the clock generator’s operating mode.
(17) MODE0 to MODE2 (Mode) ··· input
These are input pins used to specify the operating mode.
(18) RESET (Reset) ··· input
RESET is a signal that is input asynchronously and that has a constant low level width regardless of the
operating clock’s status. When this signal is input, a system reset is executed as the first priority ahead of all
other operations.
In addition to being used for ordinary initialization/start operations, this pin can also be used to release a
standby mode (HALT, IDLE, or software STOP).
(19) X1, X2 (Crystal)
These pins are used to connect the resonator that generates the system clock.
(20) CV
DD
(Power supply for clock generator)
This pin supplies positive power to the clock generator.
(21) CV
SS
(Ground for clock generator)
This is the ground pin for the clock generator.
(22) V
DD
(Power supply)
These are the positive power supply pins for each internal unit. All the V
DD
pins should be connected to a
positive power source.
(23) V
SS
(Ground)
These are ground pins. All the V
SS
pins should be grounded.
