PIC16C745/P Microchip Technology, PIC16C745/P Datasheet - Page 69

• Manufacturer Part Number: PIC16C745/P
• Description: 8-Bit CMOS Microcontrollers with USB
• Manufacturer: Microchip Technology

REGISTER 10-10: BUFFER DESCRIPTOR STATUS REGISTER. BITS WRITTEN BY THE MCU
REGISTER 10-11: BUFFER DESCRIPTOR STATUS. BITS READ BY THE MCU.
Note:
Note:
1999 Microchip Technology Inc.
bit7
bit 7:
bit 6:
bit 5-4: Reserved: Read as ’X’.
bit 3:
bit 2:
bit 1-0: Reserved: Read as ’X’.
bit7
bit 7:
bit 6:
bit 5-2: PID<3:0>: Packet Identifier. The received token PID value
bit 1-0: Reserved: Read as 'X'.
UOWN
UOWN
R/W-0
W-X
Recommend that users not use BSF, BCF due to the dual functionality of this register.
Recommend that users not use BSF, BCF due to the dual functionality of this register.
bit when it has completed a token. This byte of the BD should always be the last byte the MCU updates
when it initializes a BD. Once the BD has been assigned to the USB, the MCU should not change it in any
way.
an incorrect DTS, it will be ignored and the buffer will remain unchanged.
by the SIE that would use the BD in this location. The BD is not consumed by the SIE (the own bit remains
and the rest of the BD are unchanged) when a BSTALL bit is set.
bit when it has completed a token. This byte of the BD should always be the last byte the MCU updates
when it initializes a BD. Once the BD has been assigned to the USB, the MCU should not change it in any
way.
UOWN: USB Own. This UOWN bit determines who currently owns the buffer. The SIE writes a 0 to this
1 = USB has exclusive access to the BD. The MCU should not modify the BD or buffer.
0 = The MCU has exclusive access to the BD. The USB ignores all other fields in the BD.
DATA0/1: This bit defines the type of data toggle packet that was transmitted or received.
1 = Data 1 packet
0 = Data 0 packet
DTS: Setting this bit will enable the USB to perform Data Toggle Synchronization. If a packet arrives with
1 = Data Toggle Synchronization is performed
0 = No Data Toggle Synchronization is performed
BSTALL: Buffer Stall. Setting this bit will cause the USB to issue a STALL handshake if a token is received
UOWN: USB Own. This UOWN bit determines who currently owns the buffer. The SIE writes a 0 to this
1 = USB has exclusive access to the BD. The MCU should not modify the BD or buffer.
0 = The MCU has exclusive access to the BD. The USB ignores all other fields in the BD.
DATA0/1: This bit defines the type of data toggle packet that was transmitted or received.
1 = Data 1 packet
0 = Data 0 packet
DATA0/1
DATA0/1
R/W-X
W-X
(BDndST: 1A0h, 1A4h, 1A8h, 1ACh, 1B0h, 1B4h)
(BDndST: 1A0h, 1A4h, 1A8h, 1ACh, 1B0h, 1B4h)
R/W-X
PID3
U-X
—
R/W-X
PID2
U-X
—
Advanced Information
R/W-X
PID1
DTS
W-X
BSTALL
R/W-X
PID0
W-X
U-X
U-X
—
—
PIC16C745/765
U-X
U-X
—
—
bit0
bit0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
-n = Value at POR reset
X = Don’t care
R = Readable bit
W = Writable bit
U = Unimplemented bit,
-n = Value at POR reset
X = Don’t care
read as ‘0’
read as ‘0’
DS41124A-page 69