PixArt Imaging Inc.
PAN101B
CMOS Optical Navigation Sensor
7.2.3 Power on problem
The problem occurs if the PAN101B powers up before the microprocessor sets the SCLK and SDIO lines
to be output.
7.2.4 ESD events
The PAN101B and the micro-controller might get out of synchronization due to ESD events.
If the PAN101B and the micro-controller might get out of synchronization due to power on problem or
ESD events. An easy way to solve this is to reset PAN101B.
Power on reset to resync PAN101B
=> Reset full chip and SDIO line set to Hi-Z state)
VDD
1us,min
PD
SCLK
SDIO
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
Hi-Z
ADDRESS(R/W)
DATA
Figure 15. Power on reset to resync. PAN101B
7.3 Collision detection on SDIO
The only time that the PAN101B drives the SDIO line is during a READ operation. To avoid data
collisions, the micro-controller should release SDIO before the falling edge of SCLK after the last address
bit. The PAN101B begins to drive SDIO after the next falling edge of SCLK. The PAN101B release
SDIO of the rising SCLK edge after the last data bit. The micro-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 micro-controller should not leave SDIO floating until the next transmission (although that
will not cause any communication difficulties).
7.4 Error detection and recovery
1.The micro-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 micro-controller can verify the synchronization of the serial port by periodically reading the
product ID register.
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15
V1.4, FEB. 2003
PixArt Imaging Inc.
E-mail: fae_service@pixart.com.tw
PIXART [ PIXART IMAGING INC. ]
