14

During a read operation SCLK should be delayed at least

ADNS-3530 has time to prepare the requested data. The

falling edge of SCLK for the first address bit of either the

ter the last SCLK rising edge of the last data bit of the

previous read operation.

Burst Mode Operation

Burst mode is a special serial port operation mode that

may be used to reduce the serial transaction time for

a motion read. The speed improvement is achieved by

continuous data clocking from multiple registers with-

out the need to specify the register address, and by not

requiring the normal delay period between data bytes.

Burst mode is activated by reading the Motion_Burst

register. The ADNS-3530 will respond with the contents

of the Motion, Delta_Y, Delta_X, SQUAL, Shutter_Upper,

Shutter_Lower and Maximum_Pixel registers in that or-

der. The burst transaction can be terminated after the

first three bytes of the sequence are read by bringing

the NCS pin high. After sending the register address, the

data. All data bits can be read with no delay between

bytes by driving SCLK at the normal rate. The data is

latched into the output buffer after the last address bit

is received. After the burst transmission is complete, the

to terminate burst mode. The serial port is not available

for use until it is reset with NCS, even for a second burst

transmission.

Figure 18. Motion burst timing

Notes on Power-Up

The ADNS-3530 does not perform an internal power up

self-reset; the POWER_UP_RESET register must be writ-

ten every time power is applied. The appropriate se-

quence is as follows:

1. Apply power

2. Drive NCS high, then low to reset the SPI port

3. Write 0x5a to register 0x3a

4. Read from registers 0x02, 0x03 and 0x04 (or read

these same three bytes from burst motion register

0x42) one time regardless the state of the motion

pin.

During power-up there will be a period of time after the

power supply is high but before any clocks are available.

The table below shows the state of the various pins dur-

ing power-up and reset.

Pin

On Power-Up

NCS High Before Reset

NCS Low Before Reset

After Reset

NCS

Functional

High

Low

Functional

MISO

Undefined

Undefined

Functional

Depends on NCS

SCLK

Ignored

Ignored

Functional

Depends on NCS

MOSI

Ignored

Ignored

Functional

Depends on NCS

XY_LED

Undefined

Undefined

Undefined

Functional

MOTION

Undefined

Undefined

Undefined

Functional

SHTDWN

Must Be Low

Must Be Low

Must Be Low

Functional

MOTION_BURST REGISTER ADDRESS

READ FIRST BYTE

FIRST READ OPERATION

READ SECOND BYTE

READ THIRD BYTE

SCLK

PixArt Imaging Inc.

Low Power LED Integrated Slim Mouse Sensor

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PixArt Imaging Inc.