PixArt Imaging Inc.

PAN3204DB

Wireless Optical Mouse Sensor

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PixArt Imaging Inc.

E-mail: fae_service@pixart.com.tw

V3.0, Apr. 2008

Power On Problem - The problem occurs if the mouse sensor powers up before the mouse controller

sets the SCLK and SDIO lines to be output. The mouse sensor and the mouse controller might get out

of synchronization due to power on problem. An easy way to solve this is to use “watchdog timer

timeout”.

ESD Events - The mouse sensor and the mouse controller might get out of synchronization due to ESD

events. An easy way to solve this is to use “watchdog timer timeout”.

6.3 Collision Detection on SDIO

The only time that the mouse sensor drives the SDIO line is during a READ operation. To avoid data collisions,

the mouse controller should release SDIO before the falling edge of SCLK after the last address bit. The mouse

sensor begins to drive SDIO after the next falling edge of SCLK. The mouse sensor releases SDIO of the rising

SCLK edge after the last data bit. The mouse controller can begin driving SDIO any time after that. In order to

maintain low power consumption in normal operation or when the PD pin is pulled high, the mouse controller

should not leave SDIO floating until the next transmission (although that will not cause any communication

difficulties).

6.4 Power Down Mode

The mouse sensor can be placed in a power-down mode by setting PD_enh bit in the Configuration register via

a serial port write operation. After setting the Configuration register, wait at most 2 frames times. To get the

chip out of the power down mode, clear PD_enh bit in the Configuration register via a serial port write

operation. In the power down mode, the serial interface watchdog timer (see Section 6.2) is not available. But,

the serial interface still can read/write normally. For an accurate report after leave the power down mode, wait

about 3ms before the mouse controller is able to issue any write/read operation to the mouse sensor.

123456789

1

0

1

1

1

2

1

3

1

4

1

5

1

6

SCLK

SDIO

IDD

tPDR

2 frames, max

1

0

000

11

0

Address = 0x06

Data = 0x0C

000

011

0

0

Figure 11. Power-down Configuration Register Writing Operation

6.5 Error Detection

1. The mouse controller can verify success of write operations by issuing a read command to the same address

and comparing written data to read data.

2. The mouse controller can verify the synchronization of the serial port by periodically reading the product ID

register