VG6640 datasheet(83/126 Pages) STMICROELECTRONICS

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DocID023597 Rev 11

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VG6640, VD6640

Video system

125

7.3.5

Integration and gain parameter re-timing

Due to the triple exposure architecture and various latencies the period in the frame where a

specific register can be set to be consumed before the next frame starts is as shown in

Figure 25

Figure 25. CCI parameter update window

The last moment to update registers so that they will apply to next frame integration tracks

with the start of the next frame: 113 lines to end of current frame + 46 lines inter frame = 159

lines to before the start of next frame. If you increase the inter frame, then the moment

remains defined as: 159 lines before the start of the next frame.

7.3.6

Grouped register settings

If a large number of registers are required to be set in a single frame, due to the timing of the

CCI commands some transactions may be consumed in the immediate frame, the

remainder in the next frame. To avoid this problem, bit 0 of the Grouped_Parameter_Hold

(0x0104)

complete set of new values have been written to the sensor. Bit 0 should be set to 1,

registers written, then the bit cleared. This will ensure that all registers are consumed at the

same time. An example of the multiple CCI grouped writes is shown in Figure 26.

VG6640 数据表(PDF) 83 Page - STMicroelectronics