Public Version
Camera ISP Basic Programming Model
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6.5.6.7
Camera ISP CCDC Summary of Constraints
The following is a list of register configuration constraints to adhere to when programming the CCDC. It
can be used as a quick checklist. More detailed register setting constraints can be found in the individual
register descriptions.
•
If the memory output port is enabled, the memory output line offset and address should be on 32-byte
boundaries.
•
If faulty-pixel correction is enabled, the
address should be on a 64-byte boundary.
•
External WEN cannot be used when the VP2SDR path is enabled.
•
If the formatter is enabled, in line-alternating mode, the vertical start and end number should be even.
•
The horizontal number for the video port must be <= 1376*4.
•
If the video port is enabled,
[30:17] VERT_NUM must be
FMTLNV.
•
The video port must be enabled if the formatter is enabled.
•
In YCC input mode:
–
The
must be set to 0s.
–
The
must be set to 0s.
–
Faulty-pixel correction must be disabled.
–
The video port must be disabled.
–
The formatter must be disabled.
–
The VP2SDR must be disabled.
–
The low-pass filter must be disabled.
–
The A-Law must be disabled.
•
In RAW input mode, the resizer output path should not be enabled.
6.5.7 Programming the Preview Engine
This section discusses issues related to software control of the preview engine. It lists which registers are
required to be programmed in different modes, how to enable and disable the preview engine, and how to
check the status of the preview engine; discusses the different register access types; and enumerates
programming constraints.
6.5.7.1
Camera ISP Preview Setup/Initialization
This section discusses the configuration of the preview engine required before image processing can
begin.
6.5.7.1.1 Camera ISP Preview Reset Behavior
On hardware reset of the camera ISP, all registers in the preview engine are reset to their reset values.
However, because the preview engine programmable tables (gamma, noise filter, luminance enhancer,
and CFA coefficients) are stored in internal memory, their contents do not have reset values. If the reset is
a chip-level power-on reset (reset after power is applied), the contents of these tables are unknown. If the
reset is a camera ISP module reset (when power remains active), the contents of these tables remain the
same as before the reset.
6.5.7.1.2 Camera ISP Preview Register Setup
Before enabling the preview engine, the hardware must be correctly configured through register writes.
identifies the register parameters that must be programmed before enabling the preview
engine.
1280
Camera Image Signal Processor
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated