PIC18F24J11 MICROCHIP [Microchip Technology], PIC18F24J11 Datasheet - Page 131

• Manufacturer Part Number: PIC18F24J11
• Description: 28/44-Pin, Low-Power, High-Performance USB Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

10.0
Depending on the device selected and features
enabled, there are up to five ports available. Some pins
of the I/O ports are multiplexed with an alternate
function from the peripheral features on the device. In
general, when a peripheral is enabled, that pin may not
be used as a general purpose I/O pin.
Each port has three registers for its operation. These
registers are:
• TRIS register (Data Direction register)
• PORT register (reads the levels on the pins of the
• LAT register (Data Latch)
The Data Latch (LAT register) is useful for read-modify-
write operations on the value that the I/O pins are
driving.
Figure 10-1
port, without the interfaces to other peripherals.
FIGURE 10-1:
 2011 Microchip Technology Inc.
device)
RD LAT
Data
Bus
WR LAT
or PORT
WR TRIS
RD TRIS
RD PORT
Note 1: I/O pins have diode protection to V
I/O PORTS
displays a simplified model of a generic I/O
V
SS
TRIS Latch
Data Latch
D
D
CK
CK
.
GENERIC I/O PORT
OPERATION
Q
Q
Q
EN
EN
D
I/O pin
Buffer
Input
DD
and
(1)
PIC18F46J11 FAMILY
10.1
When developing an application, the capabilities of the
port pins must be considered. Outputs on some pins
have higher output drive strength than others. Similarly,
some pins can tolerate higher than V
10.1.1
The output pin drive strengths vary for groups of pins
intended to meet the needs for a variety of applications.
PORTB and PORTC are designed to drive higher
loads, such as LEDs. All other ports are designed for
small loads, typically indication only.
marizes the output capabilities. Refer to
“Electrical Characteristics”
TABLE 10-1:
10.1.2
The voltage tolerance of pins used as device inputs is
dependent on the pin’s input function. Pins that are used
as digital only inputs are able to handle DC voltages up
to 5.5V; a level typical for digital logic circuits. In contrast,
pins that also have analog input functions of any kind
can only tolerate voltages up to V
beyond V
2
Section 29.0 “Electrical Characteristics”
details.
TABLE 10-2:
PORTA
(except RA6)
PORTD
PORTE
PORTB
PORTC
PORTA<6>
PORTA<7:0>
PORTB<3:0>
PORTC<2:0>
PORTE<2:0>
PORTB<7:4>
PORTC<7:3>
PORTD<7:0>
Port or Pin
summarizes
Port
I/O Port Pin Capabilities
DD
PIN OUTPUT DRIVE
INPUT PINS AND VOLTAGE
CONSIDERATIONS
on these pins should be avoided.
Minimum Intended for indication.
Drive
Tolerated
OUTPUT DRIVE LEVELS
the
INPUT VOLTAGE LEVELS
High
Input
5.5V
V
DD
input
Suitable for direct LED
drive levels.
for more details.
Only V
tolerated.
Tolerates input levels
above V
most standard logic.
capabilities.
DD
Description
. Voltage excursions
DS39932D-page 131
Description
DD
DD
Table 10-1
DD
input levels.
input levels
Section 29.0
, useful for
Refer
Table 10-
for more
sum-
to