DocID018909 Rev 11
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RM0090
Digital camera interface (DCMI)
479
word. The remaining most significant bits are cleared to zero. So, in this case a 32-bit data
word is made up every two pixel clock cycles.
The first captured data are placed in the LSB position in the 32-bit word and the 2
nd
captured data are placed in the MSB position in the 32-bit word as shown in
15.5.3 Synchronization
The digital camera interface supports embedded or hardware (HSYNC & VSYNC)
synchronization. When embedded synchronization is used, it is up to the digital camera
module to make sure that the 0x00 and 0xFF values are used ONLY for synchronization
(not in data). Embedded synchronization codes are supported only for the 8-bit parallel data
interface width (that is, in the DCMI_CR register, the EDM[1:0] bits should be cleared to
“00”).
For compressed data, the DCMI supports only the hardware synchronization mode. In this
case, VSYNC is used as a start/end of the image, and HSYNC is used as a Data Valid
signal.
shows the corresponding timing diagram.
Figure 75. Timing diagram
Table 82. Positioning of captured data bytes in 32-bit words (14-bit width)
Byte address
31:30
29:16
15:14
13:0
0
0
D
n+1
[13:0]
0
D
n
[13:0]
4
0
D
n+3
[13:0]
0
D
n+2
[13:0]
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