PIC18F2550T-I/SO Microchip Technology, PIC18F2550T-I/SO Datasheet - Page 172

• Manufacturer Part Number: PIC18F2550T-I/SO
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,SOP,28PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2550T-I/SO

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 24
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 10x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Interface Type: SPI, I2C, EAUSART
• Maximum Clock Frequency: 48 MHz
• Number Of Programmable I/os: 24
• Number Of Timers: 4
• Operating Supply Voltage: 2 V to 5.5 V
• 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, ICE2000, ICE4000, DM163025, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 10 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: I3-DB18F4550 - BOARD DAUGHTER ICEPIC3DM163025 - PIC DEM FULL SPEED USB DEMO BRD
• Lead Free Status / Rohs Status: Details

PIC18F2455/2550/4455/4550
17.2.2.8
The PIC18FX455/X550 devices have a built-in 3.3V reg-
ulator to provide power to the internal transceiver and
provide a source for the internal/external pull-ups. An
external 220 nF (±20%) capacitor is required for stability.
The regulator can be enabled or disabled through the
VREGEN Configuration bit. When enabled, the voltage
is visible on pin V
set. When the regulator is disabled (VREGEN = 0), a
3.3V source must be provided through the V
the internal transceiver.
17.2.3
The USB Status register reports the transaction status
within the SIE. When the SIE issues a USB transfer
complete interrupt, USTAT should be read to determine
the status of the transfer. USTAT contains the transfer
endpoint number, direction and Ping-Pong Buffer
Pointer value (if used).
The USTAT register is actually a read window into a
four-byte status FIFO, maintained by the SIE. It allows
the microcontroller to process one transfer while the
DS39632E-page 170
Note:
Note:
Note 1: Do not enable the internal regulator if an
2: V
The drive from V
drive an external pull-up in addition to the
internal transceiver.
USB STATUS REGISTER (USTAT)
The data in the USB Status register is valid
only when the TRNIF interrupt flag is
asserted.
external regulator is connected to V
V
disabled.
Internal Regulator
USB
DD
USB
must be equal to or greater than
at all times, even with the regulator
whenever the USBEN bit is also
USB
is sufficient to only
USB
pin for
USB
.
SIE processes additional endpoints (Figure 17-4).
When the SIE completes using a buffer for reading or
writing data, it updates the USTAT register. If another
USB transfer is performed before a transaction
complete interrupt is serviced, the SIE will store the
status of the next transfer into the status FIFO.
Clearing the transfer complete flag bit, TRNIF, causes
the SIE to advance the FIFO. If the next data in the
FIFO holding register is valid, the SIE will reassert the
interrupt within 5 T
data is present, TRNIF will remain clear; USTAT data
will no longer be reliable.
FIGURE 17-4:
Note:
4-byte FIFO
for USTAT
Data Bus
If an endpoint request is received while the
USTAT
automatically issue a NAK back to the
host.
CY
USTAT from SIE
of clearing TRNIF. If no additional
FIFO
USTAT FIFO
© 2009 Microchip Technology Inc.
is
full,
Clearing TRNIF
Advances FIFO
the
SIE
will