PixArt Imaging Inc.

PAN3501UI

USB Optical Mouse Sensor Single Chip

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PixArt Imaging Inc.

V1.0, APR. 2005

4. USB Interface

4.1 USB Command Set Description (USB Descriptor)

The USB HOST detect USB mouse plug-in and assigns a new unique address to the USB mouse, then ask USB

mouse device for information about the device description, configuration description, HID report description

during enumeration period. After enumeration, the USB device is transfer motion and button value to the USB

host.

Descriptor Type

Byte

Byte

Byte

Byte

Byte

Byte

Byte

Byte

12

01

10

01

00

00

00

08

3A

09

00

25

00

01

01

02

Device Descriptor (18 bytes)

00

01

09

02

22

00

01

01

04

A0

Configuration Descriptor (9 bytes)

32

09

04

00

00

01

03

01

02

Interface Descriptor (9 bytes)

00

09

21

10

01

00

01

22

48

Human Interface Device Descriptor

(9 bytes)

00

Endpoint Descriptor (7 bytes)

07

05

81

03

04

00

0A

05

01

09

02

A1

01

05

09

19

01

29

03

15

00

25

01

95

03

75

01

81

02

95

01

75

05

81

03

05

01

09

01

A1

00

09

30

09

31

15

81

25

7F

75

08

95

02

81

06

C0

09

38

95

01

81

06

09

3C

15

00

25

01

75

01

95

Human Interface Device Report

Descriptor (72 bytes, 3D3B)

01

B1

22

95

07

B1

01

C0

4.2 USB Data Report Format

The USB report has two data formats, depending on boot or report protocol is selected. One kind of data format

is the boot protocol used in legacy environment as 4.2.1. The other kind of data format is USB report protocol

format and sends the additional wheel movement data in the fourth byte as 4.2.2. The wheel is moved forward

the fourth byte data is 01H, the wheel is moved backward the fourth byte data is FFH, and the wheel is idle the

fourth byte data is 00H.

4.2.1 USB Boot Protocol for Legacy Operation

Byte

Bit

Symbol Description

0

BL

1 = Left button pressed

1

BR

1 = Right button pressed

1

2~7

NC

Reserved

2

0-7

X0~X7

X data (D0 - D7). A positive value indicates motion to the right; a negative

value indicates motion to the left. Bit 0=LSB.

3

0-7

Y0~Y7

Y data (D0 - D7). A positive value indicates device motion upward; a negative

value indicates motion downward. Bit 0=LSB.