Microchip Technology GPIODM-KPLCD Data Sheet
PIC18F2455/2550/4455/4550
DS39632E-page 176
© 2009 Microchip Technology Inc.
REGISTER 17-5:
BDnSTAT: BUFFER DESCRIPTOR n STATUS REGISTER (BD0STAT THROUGH
BD63STAT), CPU MODE (DATA IS WRITTEN TO THE SIDE)
BD63STAT), CPU MODE (DATA IS WRITTEN TO THE SIDE)
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
R/W-x
UOWN
(1)
DTS
(2)
KEN
INCDIS
DTSEN
BSTALL
BC9
BC8
bit 7
bit 0
Legend:
R = Readable bit
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 7
UOWN: USB Own bit
(1)
0 = The microcontroller core owns the BD and its corresponding buffer
bit 6
DTS: Data Toggle Synchronization bit
(2)
1 = Data 1 packet
0 = Data 0 packet
0 = Data 0 packet
bit 5
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
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
bit 4
INCDIS: Address Increment Disable bit
1 = Address increment disabled (required for SPP endpoint configuration)
0 = Address increment enabled
1 = Address increment disabled (required for SPP endpoint configuration)
0 = Address increment enabled
bit 3
DTSEN: Data Toggle Synchronization Enable bit
1 = Data toggle synchronization is enabled; data packets with incorrect Sync value will be ignored
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
bit 2
BSTALL: Buffer Stall Enable bit
1 = Buffer stall enabled; STALL handshake issued if a token is received that would use the BD in the
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
bit 1-0
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.
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.