VV6501 Datasheet, PDF (11/60 Pages) STMicroelectronics – VGA CMOS Color Image Sensor

VV6501
Functional Description
3.1.4
Digital data bus: D[4:0]
Sensor data may be either 8 or 10 bits per pixel and is transmitted as follows:
q 10-bit data: A pair of 5-bit nibbles, most significant nibble first, on 5 wires.
q 8-bit data: A pair of 4-bit nibbles, most significant nibble first, on 4 wires.
Figure 6: Digital data output modes
5-wire output mode
D₄,D₃,D₂,D₁,D₀
4-wire output mode
D₃,D₂,D₁,D₀
10-bit pixel data
D₉,D₈,D₇,D₆,D₅
D₄,D₃,D₂,D₁,D₀
8-bit pixel data
D₇,D₆,D₅,D₄
D₃,D₂,D₁,D₀
D₉,D₈,D₇,D₆,D₅
D₇,D₆,D₅,D₄
In 5-wire mode, the embedded control codes occupy only the most significant 8-bits, the least
significant 2-bits are always zero.
Output tri-state using SIF
Register 23 bit[5] can be used to tri-state all 5 data lines, QCK and FST.
Output pad drive strength
The data and QCK output pads are tri-stateable with 4 mA drive.
3.1.5
Data qualification clock (QCK)
A data qualification clock (QCK) is available and complements the embedded control sequences.
This clock runs continuously when enabled and consists of:
q Fast QCK: the falling edge of the clock qualifies every 5 or 4-bit data blocks that constitute a
pixel value.
q Slow QCK: the rising edge qualifies 1st, 3rd, 5th, etc. blocks of data that constitute a pixel
value while the falling edge qualifies the 2nd, 4th, 6th etc. blocks of data. For example in 4-wire
mode, the rising edge of the clock qualifies the most significant nibbles while the falling edge of
the clock qualifies the least significant nibbles.
Figure 7: QCK modes
QCK (slow)
QCK (fast)
D[4:0] _{<MSB> <LSB> <MSB> <LSB> <MSB> <LSB>}
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