VT5365

ST default firmware

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3.5

SGPIO 1 - VGate

If required, (that is, if VLED > 1.8 V) SGPIO 1 can be used as a DCDC Controller output to

supply VLED. For more details please refer to STV-365-R0X user manuals.

3.6

CPI swap

The default CPI 'Counts Per Inch' of the VT5365 is 800 CPI. This can easily be toggled

between 800/1600 CPI by the user, by simply holding down the left and right buttons for 2

seconds. Once the CPI has changed, GPIO 0 will go low and turn on the Low Battery LED.

The LED turns off again as soon as one of the buttons is released.

If the batteries are removed from the mouse it will return to the default (800 CPI).

3.7

ST protocol

ST has designed their own 27 MHz RF protocol for wireless mouse applications. The coded

scheme used is the Manchester method, baud rate = 4.8 kbps.

There is support for 5 buttons, Z-wheel, 254 channel IDs + checksum.

3.8

RF ID - external EEPROM

The RF identification is stored in and read from an external EEPROM. If there is no

EEPROM fitted, then every time the mouse is powered off the user will have to reconnect

the mouse/receiver on power up.

3.9

Power management

The VT5365 is self contained, controlling everything on chip, including power management

and automatic sleep or wake-up.

The VT5365 includes several features that enable the user to choose the implementation to

maximize battery life. Typically, the MCU has the power to shut the complete chip down (with

the exception of the digital regulator, the POR and the on-chip low frequency timer). In this

mode all the clocks are OFF and the chip can wake up in two ways:

1.

Upon completion of a timer cycle (period is programmable and is set prior to going to

sleep).

2.

Upon reception of an external event, such as a state change on one of the eight main

GPIOs.

Note:

The user can program which GPIO has the ability to wake up, or not to wake up, the system.