
PIC32MX1XX/2XX
DS61168D-page 134
Preliminary
2011-2012 Microchip Technology Inc.
REGISTER 10-10: U1STAT: USB STATUS REGISTER(1)
Bit
Range
Bit
31/23/15/7
Bit
30/22/14/6
Bit
29/21/13/5
Bit
28/20/12/4
Bit
27/19/11/3
Bit
26/18/10/2
Bit
25/17/9/1
Bit
24/16/8/0
31:24
U-0U-0
—
23:16
U-0U-0
—
15:8
U-0U-0
—
7:0
R-x
U-0
ENDPT<3:0>
DIR
PPBI
—
Legend:
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 31-8 Unimplemented: Read as ‘0’
bit 7-4
ENDPT<3:0>: Encoded Number of Last Endpoint Activity bits
(Represents the number of the BDT, updated by the last USB transfer.)
1111 = Endpoint 15
1110 = Endpoint 14
0001 =Endpoint 1
0000 =Endpoint 0
bit 3
DIR: Last BD Direction Indicator bit
1 = Last transaction was a transmit transfer (TX)
0 = Last transaction was a receive transfer (RX)
bit 2
PPBI: Ping-Pong BD Pointer Indicator bit
1 = The last transaction was to the ODD BD bank
0 = The last transaction was to the EVEN BD bank
bit 1-0
Unimplemented: Read as ‘0’
Note 1: The U1STAT register is a window into a 4-byte FIFO maintained by the USB module. U1STAT value is
only valid when U1IR<TRNIF> is active. Clearing the U1IR<TRNIF> bit advances the FIFO. Data in
register is invalid when U1IR<TRNIF> = 0.