CMU Cam Low Level Register Info:

This register info may be necessary for changing the exposure settings on the CMUCam.  It seems you need to modify its low level registers in order to change the exposure settings.  Despite using ultrabright LED’s and diffusing them with half-pinpong ball coverings, the tip of the LED is still too bright.  This issue could possibly be solved by turning down the exposure of the camera, and reducing the amount of sensor saturation that occurs.  This could also help eliminate noise in the gameboard, and lend itself to using LED’s to mark other significant properties.


CMUCam CR Register-

CR [ reg1 value1 [reg2 value2 … reg16 value16] ]\r

This command sets the Camera’s internal Register values directly. The
register locations and possible settings can be found in the Omnivision
CMOS camera documentation. All the data sent to this command should
be in decimal visible character form unless the camera has previously
been set into raw mode. It is possible to send up to 16 register-value
combinations. Previous register settings are not reset between CR calls;
however, you may overwrite previous settings. Calling this command with
no arguments resets the camera and restores the camera registers to their
default state. This command can be used to hard code gain values or
manipulate other low level image properties.

Register 10 – rw: Auto-Exposure-Control Register

AEC<7:0> – exposure time setting; the formula is Interlaced: TEXPOSURE = TLINE x
AEC(7:0); Progressive: TEXPOSURE = TLINE x AEC(7:0)x2; where TLINE = Frame Time /

* This register setting is only effective when operated in manual adjust mode (register 13
bit 0=0). Nevertheless, this register is always accessible through the SCCB bus. If
register 13 bit 0=1, this register will be updated by internal circuit according AEC
algorithm, and if write special value to this register will be useless. The register value can
be read out at any time and latest AEC value will be return. If register 13 bit 0=0, or
register 29 bit 7=1, the register will hold last value unchanged (either input from SCCB or
AEC algorithm result).
It generally takes no more than two fields for the image to reach the intended exposure
after changing the setting.

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