VT5363

Configuring the VT5363

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3

Configuring the VT5363

3.1

Selecting USB or PS2 operation

The selection of USB or PS2 interface is performed [automatically] by the VT5363 including

a USB pull-up resistor connected between Pin No. 10 and the DN/DAT line.

3.2

Selecting mouse configuration

The VT5363 may be configured to be one of three different types of mouse.

●

2 button mouse

●

3 button mouse with scroll wheel

●

5 button mouse with scroll wheel

The configuration is achieved by connecting the unused switch inputs to the LNK_LED

output (pin 17). All configurations will report a USB Vendor Identity (VID) of 0x0553 (ST

Microelectronics Imaging Division). The three different configurations will result in 3 different

USB Product Identities (PIDs) and descriptor strings as described in

Table 3.

A user who wishes to use their own PID, VID and descriptor string may use an external

serial EEPROM to hold this information.

3.3

Changing the CPI

The default CPI ‘Counts Per Inch’ of the VT5363 is 800CPI, this can easily be toggled

between 800/400CPI by the user, by simply holding down the left and right buttons till

LNK_LED goes off. If the PC is shutdown or the mouse unplugged it will return to the default

(800 CPI).

3.4

External EEPROM

The VT5363 supports the use of an external 128 byte serial EEPROM for holding customer

specific information. EEPROM such as the M24C01W from STMicroelectronics are suitable.

The EEPROM must be connected to the SDA and SCL pins of the VT5363. If no EEPROM

is used then these lines should be tied to ground.The EEPROM cannot be programmed by

the VT5363 itself and must be pre-programmed before being fitted to the final PCB.

Table 3.

Configuration selection

Mode

Inputs tied to

LNK_LED

VID

PID

USB descriptor string

2 button

SWBACK,

SWFOR, SWMID

0x0553

0x0A00

‘2 button optical mouse’

3 button + Z

SWBACK, SWFOR

0x0553

0x0A01

‘3 button optical mouse with scroll

wheel’

5 button + Z

none

0x0553

0x0A02

‘5 button optical mouse with scroll

wheel’