UPD784218 Datasheet, PDF (32/92 Pages) NEC – 16-/8-BIT SINGLE-CHIP MICROCONTROLLERS

µPD784218, 784218Y
Table 8-1. Port Functions
Port Name
Port 0
Port 1
Port 2
Port 3
Port 4
Port 5
Port 6
Port 7
Port 8
Port 9
Port 10
Port 12
Port 13
Pin Name
Function
Specification of Pull-up Resistor
Connection by Software
P00 to P06 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P10 to P17 • Input port
—
P20 to P27 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P30 to P37 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P40 to P47
• Can be set in input or output mode in 1-bit units Can be specified in 1-port units
• Can directly drive LEDs
P50 to P57
• Can be set in input or output mode in 1-bit units Can be specified in 1-port units
• Can directly drive LEDs
P60 to P67 • Can be set in input or output mode in 1-bit units Can be specified in 1-port units
P70 to P72 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P80 to P87 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P90 to P95 • N-ch open-drain I/O port
—
• Can be set in input or output mode in 1-bit units
• Can directly drive LEDs
P100 to P103 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P120 to P127 • Can be set in input or output mode in 1-bit units Can be specified in 1-bit units
P130, P131 • Can be set in input or output mode in 1-bit units
—
8.2 Clock Generator
An on-chip clock generator necessary for operation is provided. This clock generator has a frequency divider.
If high-speed operation is not necessary, the internal operating frequency can be lowered by the frequency divider
to reduce the current consumption.
Figure 8-2. Clock Generator Block Diagram
XT1
Subsystem
clock
fXT
XT2
oscillator
X1
Main system
clock
IDLE
fX
X2
oscillator
controller
Frequency
divider _fX
2
STOP, bit 2 of standby
control register (STBC)
(MCK) = 1 when
subsystem clock is
selected as CPU clock
Prescaler
fXX
fXX fXX fXX
2 2² 2³
Prescaler
Watch timer,
clock output
function
Clock to
peripheral
hardware
STOP,
IDLE
controller
HALT
controller
CPU
clock
(fCPU)
Internal system
clock (fCLK)
32
Data Sheet U12304EJ2V0DS00