PIC18F2455_09 Datasheet, PDF (178/438 Pages) Microchip Technology – 28/40/44-Pin,High-Performance,Enhanced Flash,USB Microcontrollers with nanoWatt Technology

PIC18F2455/2550/4455/4550
REGISTER 17-5: BDnSTAT: BUFFER DESCRIPTOR n STATUS REGISTER (BD0STAT THROUGH
BD63STAT), CPU MODE (DATA IS WRITTEN TO THE SIDE)
R/W-x
UOWN⁽¹⁾
bit 7
R/W-x
DTS⁽²⁾
R/W-x
KEN
R/W-x
INCDIS
R/W-x
DTSEN
R/W-x
BSTALL
R/W-x
BC9
R/W-x
BC8
bit 0
Legend:
R = Readable bit
-n = Value at POR
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1-0
UOWN: USB Own bit⁽¹⁾
0 = The microcontroller core owns the BD and its corresponding buffer
DTS: Data Toggle Synchronization bit⁽²⁾
1 = Data 1 packet
0 = Data 0 packet
KEN: BD Keep Enable bit
1 = USB will keep the BD indefinitely once UOWN is set (required for SPP endpoint configuration)
0 = USB will hand back the BD once a token has been processed
INCDIS: Address Increment Disable bit
1 = Address increment disabled (required for SPP endpoint configuration)
0 = Address increment enabled
DTSEN: Data Toggle Synchronization Enable bit
1 = Data toggle synchronization is enabled; data packets with incorrect Sync value will be ignored
except for a SETUP transaction, which is accepted even if the data toggle bits do not match
0 = No data toggle synchronization is performed
BSTALL: Buffer Stall Enable bit
1 = Buffer stall enabled; STALL handshake issued if a token is received that would use the BD in the
given location (UOWN bit remains set, BD value is unchanged)
0 = Buffer stall disabled
BC9:BC8: Byte Count 9 and 8 bits
The byte count bits represent the number of bytes that will be transmitted for an IN token or received
during an OUT token. Together with BC<7:0>, the valid byte counts are 0-1023.
Note 1: This bit must be initialized by the user to the desired value prior to enabling the USB module.
2: This bit is ignored unless DTSEN = 1.
DS39632E-page 176
© 2009 Microchip Technology Inc.