PIC18F25J50 MICROCHIP [Microchip Technology], PIC18F25J50 Datasheet - Page 357

• Manufacturer Part Number: PIC18F25J50
• Description: 28/44-Pin, Low-Power, High-Performance USB Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

22.0
This section describes the details of the USB peripheral.
Because of the very specific nature of the module,
knowledge of USB is expected. Some high-level USB
information is provided in
USB”
are encouraged to refer to the official specification
published by the USB Implementers Forum (USB-IF) for
the latest information. “USB Specification Revision 2.0”
is the most current specification at the time of publication
of this document.
FIGURE 22-1:
 2011 Microchip Technology Inc.
Note 1: The internal pull-up resistors should be disabled (UPUEN = 0) if external pull-up resistors are used.
USB Clock from the
Oscillator Module
USB Control and
USB RAM
3.8-Kbyte
only for application design reference. Designers
Configuration
UNIVERSAL SERIAL BUS
(USB)
USB PERIPHERAL AND OPTIONS
PIC18F46J50 Family
Section 22.9 “Overview of
UTRDIS
UPUEN
USB
SIE
FSEN
Transceiver
Internal Pull-ups
FS
P
PIC18F46J50 FAMILY
P
22.1
PIC18F46J50 family devices contain a full-speed and
low-speed, compatible USB Serial Interface Engine
(SIE) that allows fast communication between any USB
host and the PIC
directly to the USB, utilizing the internal transceiver.
Some special hardware features have been included to
improve performance. Dual access port memory in the
device’s data memory space (USB RAM) has been
supplied to share direct memory access between the
microcontroller core and the SIE. Buffer descriptors are
also provided, allowing users to freely program end-
point memory usage within the USB RAM space.
Figure 22-1
peripheral and its features.
V
USB
Overview of the USB Peripheral
D+
D-
provides a general overview of the USB
Pull-ups
Optional
External
Speed)
(Full
®
MCU. The SIE can be interfaced
(1)
Speed)
(Low
External 3.3V
Supply
DS39931D-page 357
USB Bus