zic2410 California Eastern Laboratories, zic2410 Datasheet - Page 52

• Manufacturer Part Number: zic2410
• Description: Single-chip Solution, Compliant With Zigbee
• Manufacturer: California Eastern Laboratories

ZIC2410 Datasheet
1.7.10 QUAD DECODER
The Quad Decoder block notifies the MCU of the counter value based on the direction and
movement of a pointing device, such as a mouse, after receiving a Quadrature signal from the
pointing device.
Quadrature signal is changed with 90° phase difference (1/4 period) between two signals as
shown in Figure 26 In addition, counter value means 1/4 of one period. Since this block can
receive three Quadrature signals, it can support not only the two-dimensional movement such
as mouse but also the pointing device which is in three dimensions.
Figure 26, (a) shows that the XA signal is changing before the XB signal. In this case, the
pointing device is moving in the down direction. Drawing (b) shows that the XB signal is
changing before the XA signal. In this case, the pointing device is moving in the up direction.
The rules for YA, YB, ZA and ZB are the same as described above for XA and XB.
(a)
(b)
Figure 26 – Quadrature Signal Timing between XA and XB.
Rev A
Document No. 0005-05-07-00-000
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