9 i/O PORTS (P)
S1C17153 TeChniCal Manual
Seiko epson Corporation
9-1
(Rev. 1.0)
I/O Ports (P)
9
P Module Overview
9.1
The P ports are general-purpose digital inputs/outputs that allow software to control the input/output direction and
pull-up resistor. These ports are shared with internal peripheral module inputs/outputs, and the pin functions can be
switched by setting the registers. A number of port groups can generate interrupts caused by a transition of the input
signal.
The following shows the features of the P module:
• Maximum 12 I/O ports (P0[7:0], P1[3:0]) are available.
* The number of ports for general-purpose use depends on the peripheral functions used.
• Each port has a pull-up resistor that can be enabled with software.
• Input interface level: CMOS Schmitt
• The P0 ports can generate input interrupts at the signal edge selected with software.
• The P0 ports include a chattering filter.
• Can generate an initial reset by entering low level simultaneously to the P0 ports selected with software.
• All port provide a port function select bit to configure the pin function (for GPIO or peripheral functions).
Figure 9.1.1 shows the I/O port configuration.
Peripheral output
Peripheral I/O control
P
x
PU
y
P
x
OEN
y
P
x
OUT
y
P
xy
MUX
Pull-up enable
Output enable
Output data
Function selection
V
DD
V
SS
Internal data bus
P
xy
Peripheral module input
P
x
IEN
y
P0CF1[2:0]/P0CF2[2:0]
Chattering filter
(P0)
Input enable
1.1 I/O Port Configuration
Figure 9.
notes
: • The PCLK clock must be supplied from the clock generator to access the I/O port. The PCLK
clock is also needed to operate the P0 chattering filter.
• The “
xy
” in the register and bit names refers to the port number (P
xy
,
x
= 0 and 1,
y
= 0 to 7).
Example: P
x
IN
y
/P
x
_IN register
P00: P0IN0/P0_IN register
P13: P1IN3/P1_IN register