ADNS-2030 Avago Technologies US Inc., ADNS-2030 Datasheet - Page 18

• Manufacturer Part Number: ADNS-2030
• Description: Optical Mouse Sensor,DIP
• Manufacturer: Avago Technologies US Inc.

Specifications of ADNS-2030

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Forcing the SDIO Line to the Hi-Z State
There are times when the SDIO line from the ADNS-2030
should be in the Hi-Z state. If the microprocessor has com-
pleted a write to the ADNS-2030, the SDIO line is Hi-Z, since
the SDIO pin is still configured as an input. However, if the
last operation from the microprocessor was a read, the
ADNS-2030 will hold the D0 state on SDIO until a falling
edge of SCLK.
To place the SDIO pin into the Hi-Z state, first raise the
PD pin for 100 µs (min). The PD pin can stay high, with
the ADNS-2030 in the shutdown state, or the PD pin can
be lowered, returning the ADNS-2030 to normal opera-
tion. In either case, the SDIO line will now be in the Hi-Z
state.
Figure 29. SDIO Hi-Z state and timing.
Figure 30. Timing between two write commands.
Figure 31. Timing between write and read commands.
Figure 32. Timing between read and either write or subsequent read commands.
1
SDIO
SCLK
SCLK
SCLK
PD
100 s
Address
Address
Address
Write Operation
Write Operation
Hi-Z
Data
Data
Read Operation
t
100 s
HOLD
Address
Required Timing Between Read and Write Commands
There are minimum timing requirements between read
and write commands on the serial port. See Figure 30.
If the rising edge of SCLK for the last data bit of the sec-
ond write command occurs before the 100 microsecond
required delay, then the first write command may not
complete correctly. See Figure 31.
If the rising edge of SCLK for the last address bit of the
read command occurs before the 100 microsecond re-
quired delay, then the write command may not complete
correctly. See Figure 32.
t
100 s
100 s
t
SWW
SWR
Write Operation
Address
Data
Data
Next Read
Operation
t
SRW
>120 ns
and t
Write Operation
SRR
Next Read or
Address