XR21V1410
25
REV. 1.4.0
1-CH FULL-SPEED USB UART
T
ABLE
16: I
NTERRUPT
P
ACKET
F
ORMAT
T
ABLE
17: D
ATA
F
IELD OF
S
TANDARD
I
NTERRUPT
P
ACKET
If the Exar vendor specific packet mapping is enabled then the data field also includes status for all of the
UART / GPIO pins as follows:
O
FFSET
F
IELD
S
IZE
(B
YTES
)
V
ALUE
D
ESCRIPTION
0 bmRequestType 1 8’b10100001 D7 = Device-to-host direction
D6:5 = Class Type
D4-0: = Interface Recipient
1 bNotification 1 8’h20 Defined encoding for SERIAL_STATE
2 wValue 2 16’h0000
4 wIndex 2 16’h0000 D15-8 = Reserved (0)
D7-0 = Interface number, 8’h00 for the CDC Com-
mand Interface
6 wLength 2 16’h0002 2 bytes of transferred data
8 Data 2 Standard
int_status
(See
Table 17
or
Table 18
)
D15-7 = Reserved (0)
D6 = bOverRun
D5 = bParity
D4 = bFraming
D3 = bRingSignal (RI)
D2 = bBreak
D1 = bTxCarrier (DSR)
D0 = bRxCarrier (CD)
B
IT
(
S
) F
IELD
D
ESCRIPTION
D15..D7 Reserved (0)
D6 bOverRun Received data has been discarded due to overrun in the device.
D5 bParity A parity error has occured.
D4 bFraming A framing error has occured.
D3 bRingSignal State of ring signal detection of the device.
D2 bBreak State of break detection mechanism of the device.
D1 bTxCarrier State of transmission carrier. This signal corresponds to V.24 signal 106 and
RS-232 signal DSR.
D0 bRxCarrier State of receiver carrier detection mechanism of device. This signal corre-
sponds to V.24 signal 109 and RS-232 signal DCD.
