目的:禁用AEC(auto-exposure control,自动曝光控制),自己设定曝光时间 问题:从DataSheet上发现AEC控制寄存器有两个,分别如下 Address RegisterName DefaultValue R/W Description 13 COM8 8F RW Common control 8 其中 Bit[7]: Enable fast AGC/AEC algorithm Bit[6]: AEC-Step size limit(used only in fast condition and COM5[0] is low) 0: Fast condition change maximum step is VSYNC 1: Unilimted step size Bit[5]: Band filtering ON/OFF Bit[4]: Reserved Bit[3]: Enable AEC time can be less than 1 line option Bit[2]: AGC enable Bit[1]: AWB enable Bit[0]: AEC enable
14 COM9 4A RW Common Control 9 其中 Bit[7]: reserved Bit[6:4]: Automatic gain Ceiling-Maximum AGC value Bit[3]: Exposure timing can be less than limit of banding filter when light is too strong Bit[2]: Data format - VSYNC drop option 0: VSYNC always exists 1: VSYNC will drop when frame data drops Bit[1]: Enable drop frame when AEC step is larger than VSYNC Bit[0]: Freeze AGC/AEC
控制AEC值的寄存器如下, 04 COM1 00 RW Common Control 1 其中 Bit[1:0]: AEC low 2 LSB(See Register AECHM for AEC[15:10],and AECH for AEC[9:2])
10 AECH 40 RW Exposure value 其中 Bit[7:0]: AEC[9:2](see register AECHM for AEC[15:10] COM1 for AEC[1:0]
A1 AECHM 40 RW Exposure value 其中 Bit[7:6]: reserved Bit[5:0]: AEC[15:10]
通过设置COM8中的Bit[0]为1和0可以分别启用和禁用AEC功能,但无论是否启用AEC读出的AEC值都为0x100,最初初始化时AEC的值为0x00, 并且拍摄过程中无论向AEC值寄存器中写入什么值读出的总是0x100。请问当我禁用AEC功能时应该控制哪些寄存器来设定曝光时间。 网上的资料说ov的曝光时间是通过控制行频(HSYNC)来控制曝光时间,是否要找到此类寄存器,DataSheet上好像没有说明。哪位有经验的朋友请指教,不胜感激!谢谢!
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