PIC18F25J50-I/SS Microchip Technology, PIC18F25J50-I/SS Datasheet - Page 12

• Manufacturer Part Number: PIC18F25J50-I/SS
• Description: IC PIC MCU FLASH 32K 2V 28-SSOP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F25J50-I/SS

• Program Memory Type: FLASH
• Program Memory Size: 32KB (16K x 16)
• Package / Case: 28-SSOP
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 16
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 2.15 V ~ 3.6 V
• Data Converters: A/D 10x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3776 B
• Interface Type: EUSART, I2C, SPI
• Maximum Clock Frequency: 48 MHz
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, DM183022, DM183032, DV164136, MA180024
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 10 Channel
• Package: 28SSOP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 48 MHz
• Operating Supply Voltage: 2.5|3.3 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164322 - MODULE SOCKET MPLAB PM3 28/44QFN
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

1.3
© 2008 Microchip Technology Inc.
USB DEVICE FIRMWARE IN THE FRAMEWORK
Although the USB-specific registers are similar between all of the different Microchip
USB products, a few differences still exist. For example, when configured for a
PLL-Based Oscillator mode, the PIC18F4550 will power-up by default with the PLL
enabled. On the PIC18F87J50 family of devices, the PLL is initially disabled even when
configured for a PLL-Based Oscillator mode. If the USB module clock is being derived
from the PLL, user firmware must set the PLLEN bit (OSCTUNE<6>) bit at least
two milliseconds before enabling the USB module.
To accommodate these types of differences, the source code for the Framework uses
#if defined statements based on the processor to change the code accordingly.
The selection of the demo board is found in the HardwareProfile.h file of the
example code.
If developing for a non-Microchip demo board platform, additional changes may also
be needed. The example framework projects make use of the hardware features
available on the demo boards, such as LEDs, push buttons, temperature sensor,
RS-232 connector, etc. When developing for a different platform, these aspects of the
projects will either need to be replaced or removed. The HardwareProfile.h
file maps functions to pin names and will likely need modification. See
Section 1.3.1.3 “HardwareProfile.h” for more details.
As seen in the directory structure section above, there are three main folders
associated with the USB Device Framework:
• The application folder, “<Application>”
• The USB Framework source folder, Microchip\USB
• The Framework header folder, Microchip\Include\USB
Both the application folder and the Framework folders will be discussed in detail.
1.3.1
The application folder contains the application-specific information. This includes the
configuration information specific to this project, the application code itself, the USB
descriptors and the MPLAB IDE associated files.
1.3.1.1
This header file is a key element to the configuration of the USB stack. It defines vari-
ous parameters inside the stack that determine how the stack will operate and which
optional features to include. Changing these options can have implications of code
size, RAM usage and data throughput. USB_SUPPORT_DEVICE is the definition that
enabled the entire device/peripheral stack. Without this definition, the stack will not run
in Device mode.
• EP0_BUFF_SIZE defines the buffer size for Endpoint 0. It can have a valid value
• MAX_NUM_INT defines the size of the array which keeps track of the active
of 8, 16, 32 or 64 bytes. This definition is used globally in the project for many
things. It is used during project build to allocate appropriate buffer size for
Endpoint 0. It is used in the USB descriptor to notify the USB host of the size of
the Endpoint 0 buffer. It is also used during control transfer operation.
When defining this variable, note that a low-speed USB device can only use an
8-byte buffer, while a full-speed USB device can use an 8, 16, 32 or 64-byte buffer.
alternate setting for each interface, which can be switched during operation. Valid
values are integers [0, 1, 2,...]. If a device has multiple configurations, the number
of interfaces from the configuration with the highest number of interfaces should
be used. For example, a device with two configurations has three interfaces in the
first configuration and two interfaces in the second. In this case, MAX_NUM_INT
should be three.
Application Folder
usb_config.h
DS51679B-page 8