PIC16C745SLASHP datasheet(69/158 Pages) MICROCHIP

69 / 158 page

Advanced Information

DS41124A-page 69

PIC16C745/765

(BDndST: 1A0h, 1A4h, 1A8h, 1ACh, 1B0h, 1B4h)

W-X

U-X

W-X

U-X

UOWN

DATA0/1

—

DTS

BSTALL

—

R = Readable bit

W = Writable bit

U = Unimplemented bit,

read as ‘0’

-n = Value at POR reset

X = Don’t care

bit7

bit0

bit 7:

UOWN: USB Own. This UOWN bit determines who currently owns the buffer. The SIE writes a 0 to this

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.

= USB has exclusive access to the BD. The MCU should not modify the BD or buffer.

= The MCU has exclusive access to the BD. The USB ignores all other fields in the BD.

bit 6:

DATA0/1: This bit defines the type of data toggle packet that was transmitted or received.

= Data 1 packet

= Data 0 packet

bit 5-4:

Reserved: Read as ’X’.

bit 3:

DTS: Setting this bit will enable the USB to perform Data Toggle Synchronization. If a packet arrives with

an incorrect DTS, it will be ignored and the buffer will remain unchanged.

= Data Toggle Synchronization is performed

= No Data Toggle Synchronization is performed

bit 2:

BSTALL: Buffer Stall. Setting this bit will cause the USB to issue a STALL handshake if a token is received

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 1-0:

Reserved: Read as ’X’.

Note:

Recommend that users not use BSF, BCF due to the dual functionality of this register.

R/W-0

R/W-X

U-X

UOWN

DATA0/1

PID3

PID2

PID1

PID0

—