PIC18F2450-I/SO Microchip Technology, PIC18F2450-I/SO Datasheet - Page 140

• Manufacturer Part Number: PIC18F2450-I/SO
• Description: IC PIC MCU FLASH 8KX16 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2450-I/SO

• Program Memory Type: FLASH
• Program Memory Size: 16KB (8K x 16)
• Package / Case: 28-SOIC (7.5mm Width)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: UART/USART, USB
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 23
• Ram Size: 768 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
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 768 B
• Interface Type: EUSART/USB
• Maximum Clock Frequency: 48 MHZ
• Number Of Programmable I/os: 23
• Number Of Timers: 3
• 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, DM163014, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit
• Package: 28SOIC W
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 48 MHz
• A/d Bit Size: 10 bit
• A/d Channels Available: 10
• Height: 2.31 mm
• Length: 17.87 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2 V
• Width: 7.49 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164322 - MODULE SOCKET MPLAB PM3 28/44QFNDM163025 - PIC DEM FULL SPEED USB DEMO BRD
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC18F2450/4450
When UOWN is set, the user can no longer depend on
the values that were written to the BDs. From this point,
the SIE updates the BDs as necessary, overwriting the
original BD values. The BDnSTAT register is updated
by the SIE with the token PID and the transfer count,
BDnCNT, is updated.
The BDnSTAT byte of the BDT should always be the
last byte updated when preparing to arm an endpoint.
The SIE will clear the UOWN bit when a transaction
has completed. The only exception to this is when KEN
is enabled and/or BSTALL is enabled.
No hardware mechanism exists to block access when
the UOWN bit is set. Thus, unexpected behavior can
occur if the microcontroller attempts to modify memory
when the SIE owns it. Similarly, reading such memory
may produce inaccurate data until the USB peripheral
returns ownership to the microcontroller.
14.4.1.2
When UOWN = 0, the microcontroller core owns the
BD. At this point, the other seven bits of the register
take on control functions.
The
(BDnSTAT<3>), controls data toggle parity checking.
Setting DTSEN enables data toggle synchronization by
the SIE. When enabled, it checks the data packet’s
parity against the value of DTS (BDnSTAT<6>). If a
packet arrives with an incorrect synchronization, the
data will essentially be ignored. It will not be written to
TABLE 14-3:
DS39760C-page 138
DATA0
DATA1
DATA1
DATA0
Either
Either, with error
Legend: x = don’t care
OUT Packet
from Host
Data
BDnSTAT Register (CPU Mode)
Toggle
EFFECT OF DTSEN BIT ON ODD/EVEN (DATA0/DATA1) PACKET RECEPTION
Sync
DTSEN
BDnSTAT Settings
1
1
1
1
0
x
Enable
DTS
0
0
1
1
x
x
bit,
DTSEN
Handshake
Preliminary
ACK
ACK
ACK
ACK
ACK
NAK
Device Response after Receiving Packet
UOWN
the USB RAM and the USB transfer complete interrupt
flag will not be set. The SIE will send an ACK token
back to the host to Acknowledge receipt, however. The
effects of the DTSEN bit on the SIE are summarized in
Table 14-3.
The Buffer Stall bit, BSTALL (BDnSTAT<2>), provides
support for control transfers, usually one-time stalls on
Endpoint 0. It also provides support for the
SET_FEATURE/CLEAR_FEATURE commands speci-
fied in Chapter 9 of the USB specification; typically,
continuous STALLs to any endpoint other than the
default control endpoint.
The BSTALL bit enables buffer stalls. Setting BSTALL
causes the SIE to return a STALL token to the host if a
received token would use the BD in that location. The
EPSTALL bit in the corresponding UEPn control
register is set and a STALL interrupt is generated when
a STALL is issued to the host. The UOWN bit remains
set and the BDs are not changed unless a SETUP
token is received. In this case, the STALL condition is
cleared and the ownership of the BD is returned to the
microcontroller core.
The BD9:BD8 bits (BDnSTAT<1:0>) store the two most
significant digits of the SIE byte count; the lower 8 digits
are stored in the corresponding BDnCNT register. See
Section 14.4.2
information.
0
1
0
1
0
1
TRNIF
1
0
1
0
1
0
“BD
BDnSTAT and USTAT Status
© 2007 Microchip Technology Inc.
Byte
Not Updated
Not Updated
Not Updated
Updated
Updated
Updated
Count”
for
more