Datasheet
78K0/Kx2-L CHAPTER 2 PIN FUNCTIONS
R01UH0028EJ0400 Rev.4.00 50
Sep 27, 2010
2.2.8 P120 to P125 (port 12)
P120 functions as an I/O port. P121 to P125 function as an Input port. These pins also function as pins for external
interrupt request input, potential input for external low-voltage detection, connecting resonator for main system clock,
connecting resonator for subsystem clock, external clock input for main system clock, external clock input for subsystem
clock, external reset input, and clock input and data I/O for flash memory programmer/on-chip debugger.
Set bit 5 (RSTM) of the reset pin mode register (RSTMASK) to 1 when using P125/RESET as an input port, and clear
RSTM to 0 when using P125/RESET as an external reset input.
Furthermore, the timer input and external interrupt request input can be assigned to P121 of the 78K0/KA2-L (25-pin
products) and P121 and P125 of the 78K0/KA2-L (32-pin products) by setting the port alternate switch control register
(MUXSEL). The data output of the serial interface can be assigned to P120 of the 78K0/KC2-L (44-pin and 48-pin
products) by setting the port alternate switch control register (MUXSEL).
78K0/KY2-L
(
μ
PD78F055x)
78K0/KA2-L
(
μ
PD78F056x)
78K0/KB2-L
(
μ
PD78F057x)
78K0/KC2-L
(
μ
PD78F058x)
16 Pins 20 Pins 25 Pins 32 Pins 30 Pins 40 Pins 44, 48 Pins
− − − −
P120/EXLVI/
INTP0
P120/EXLVI/
INTP0
P120/EXLVI/
INTP0(/SO11)
P121/X1/
TOOLC0
P121/X1/
TOOLC0
P121/X1/
TOOLC0
(/TI000)
(/INTP0)
P121/X1/
TOOLC0
(/TI000)
(/INTP0)
P121/X1/
TOOLC0
P121/X1/
TOOLC0
P121/X1/
TOOLC0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
P122/X2/
EXCLK/
TOOLD0
− − − − −
P123/XT1 P123/XT1
− − − − −
P124/XT2/
EXCLKS
P124/XT2/
EXCLKS
P125/RESET P125/RESET P125/RESET P125/RESET
(/TI000)
(/INTP0)
P125/RESET P125/RESET P125/RESET
Remark Functions in parentheses ( ) can be assigned by setting the port alternate switch control register (MUXSEL).
The following operation modes can be specified in 1-bit units.
(1) Port mode
P120 to P125 function as an I/O port. P120 to P125 can be set to input or output port using port mode register 12
(PM12). Only for P120 and P125, use of an on-chip pull-up resistor can be specified by pull-up resistor option register
12 (PU12).
(2) Control mode
P120 to P125 function as pins for external interrupt request input, potential input for external low-voltage detection,
connecting resonator for main system clock, connecting resonator for subsystem clock, external clock input for main
system clock, external clock input for subsystem clock, external reset input, and clock input and data I/O for flash
memory programmer/on-chip debugger.
<R>
<R>