CHAPTER 2 PIN FUNCTIONS
41
User’s Manual U15195EJ5V0UD
(14) MODE0, MODE1 (Mode) … Input
These are the input pins that specify the operation mode. Operation modes are broadly divided into normal
operation modes and flash memory programming mode. The normal operation modes are single-chip mode
and ROMless mode (see
3.3 Operation Modes
for details). The operation mode is determined by sampling
the status of each of the MODE0 and MODE1 pins on a reset.
Fix these pins so that the input level does not change during operation.
(a)
µ
PD703114
MODE1 MODE0
Operation
Mode
L L
ROMless
mode
L H
Normal operation mode
Single-chip mode
Other than above
Setting prohibited
(b)
µ
PD70F3114
MODE1/V
PP
MODE0
Operation
Mode
L L
ROMless
mode
L H
Normal operation mode
Single-chip mode
7.8 V
H
Flash memory programming mode
Other than above
Setting prohibited
Remark
L: Low-level input
H: High-level input
(15) RESET (Reset) … Input
RESET input is asynchronous input. When a signal having a certain low level width is input in asynchronous
with the operation clock, a system reset that takes precedence over all operations occurs.
Besides a normal initialize or start, this signal is also used to release a standby mode (HALT, IDLE, software
STOP).
(16) X1, X2 (Crystal)
These pins connect a resonator for system clock generation.
They can also input external clocks. In this case, connect the external clock to the X1 pin and leave the X2
pin open.
(17) CV
SS
(Ground for clock generator)
This is the ground pin for the resonator, PLL and regulator.
(18) V
DD
(Power supply)
This is the 5 V system positive power supply pin for the peripheral interface.
(19) V
SS
(Ground)
This is the 5 V system ground pin for the peripheral interface.