79980d9c98
This patch simply adds a newline character at end-of-file to those files in Documentation/ that currently lack one. This is done for a few different reasons: A) It's rather annoying when you do "cat some_file.txt" that your prompt/cursor ends up at the end of the last line of output rather than on a new line. B) Some tools that process files line-by-line may get confused by the lack of a newline on the last line. C) The "\ No newline at end of file" line in diffs annoys me for some reason. So, let's just add the missing newline once and for all. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
38 lines
2.3 KiB
Text
38 lines
2.3 KiB
Text
Programmer's View of Cpia2
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Cpia2 is the second generation video coprocessor from VLSI Vision Ltd (now a
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division of ST Microelectronics). There are two versions. The first is the
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STV0672, which is capable of up to 30 frames per second (fps) in frame sizes
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up to CIF, and 15 fps for VGA frames. The STV0676 is an improved version,
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which can handle up to 30 fps VGA. Both coprocessors can be attached to two
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CMOS sensors - the vvl6410 CIF sensor and the vvl6500 VGA sensor. These will
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be referred to as the 410 and the 500 sensors, or the CIF and VGA sensors.
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The two chipsets operate almost identically. The core is an 8051 processor,
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running two different versions of firmware. The 672 runs the VP4 video
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processor code, the 676 runs VP5. There are a few differences in register
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mappings for the two chips. In these cases, the symbols defined in the
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header files are marked with VP4 or VP5 as part of the symbol name.
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The cameras appear externally as three sets of registers. Setting register
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values is the only way to control the camera. Some settings are
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interdependant, such as the sequence required to power up the camera. I will
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try to make note of all of these cases.
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The register sets are called blocks. Block 0 is the system block. This
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section is always powered on when the camera is plugged in. It contains
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registers that control housekeeping functions such as powering up the video
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processor. The video processor is the VP block. These registers control
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how the video from the sensor is processed. Examples are timing registers,
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user mode (vga, qvga), scaling, cropping, framerates, and so on. The last
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block is the video compressor (VC). The video stream sent from the camera is
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compressed as Motion JPEG (JPEGA). The VC controls all of the compression
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parameters. Looking at the file cpia2_registers.h, you can get a full view
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of these registers and the possible values for most of them.
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One or more registers can be set or read by sending a usb control message to
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the camera. There are three modes for this. Block mode requests a number
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of contiguous registers. Random mode reads or writes random registers with
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a tuple structure containing address/value pairs. The repeat mode is only
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used by VP4 to load a firmware patch. It contains a starting address and
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a sequence of bytes to be written into a gpio port.
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