XR22801 Datasheet, PDF (31/42 Pages) Exar Corporation – Hi-Speed USB to 10/100 Ethernet Bridge

I2C_SLAVE_IN
Transfer Type: Interrupt In
Transfer Size: 37 bytes
Interrupt in packet status only, or status and read data from the I2C interface.
XR22801
Field
Report ID
Flags
WrSize
RdSize
Reserved
Data
Offset
0
1
Size
1
1
Value
0x00
Bitmap
2
1
Number
3
1
Number
4
1
0x00
5
32
Data
Description
I²C response packet
Status of the requested transfer.
D0: Request Error. If 1, the OUT request had an error (e.g. invalid size)
and was not executed.
D1: A byte sent to a slave received an I2C NAK response. The transfer
was aborted.
D2: Arbitration was lost. The transfer was aborted.
D3: Timeout. Bus free condition was not observed within 256 ms or an
individual byte transfer extended longer than 10ms.
D7..D4: Sequence number. This number matches the value provided in
the corresponding OUT command packet.
Number of bytes written, 0 to 32.
Number of bytes read, 0 to 32.
This field is reserved and should always return a value of 0x00.
The read data that was received from the slave. HID uses a fixed report
size for each specific report ID, so this field will always be 32 bytes long.
However, only the number of bytes specified in RdSize are valid. Other
bytes should be ignored.
Feature Reports
Access to XR22801 registers via HID feature reports along with the register descriptions are given in the following sections.
WRITE_HID_REGISTER
Transfer Type: Control
Transfer Size: 5 bytes
The WRITE_HID_REGISTER report writes 2 bytes of data to the specified register address.
Field
Report ID
Write Address LSB
Write Address MSB
Write Data LSB
Write Data MSB
Offset
0
1
2
3
4
Size
1
1
1
1
1
Value
0x3C
Write HID register
Write address
Write data
Description
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