STM32 Discovery+OV2640 image too dark

[butterflyeffect3d]

Posted on October 28, 2013 at 04:14

Hi everybody,

I'm working with OV2640 and i've problem with brightness. I use TFT LCD to display, use config from STM32F4xx_DSP_StdPeriph_Lib ( dcmi_ov2640.c). DMA and DCMI working fine but the image i receive too dark. So, i use :

void OV2640_BrightnessConfig(uint8_t Brightness)

{

  OV2640_WriteReg(0xff, 0x00);

  OV2640_WriteReg(0x7c, 0x00);

  OV2640_WriteReg(0x7d, 0x04);

  OV2640_WriteReg(0x7c, 0x09);

  OV2640_WriteReg(0x7d, Brightness);

  OV2640_WriteReg(0x7d, 0x00);

}

to increase brightness but the image still dark. I check datasheet of ov2640 for 0x7c and 0x7d reg but i can't find it. I think the config for this ov2640 is wrong, i want to correct it but they config a lot of regs that doesn't describe in the datasheet. I'm going to contact ovt for these reg setting, hope they answer...

[Tesla DeLorean]

Posted on October 28, 2013 at 14:47

Not much support here for cameras. And I don't suppose OVT provides support to random users. If you're commercial push through usual distribution and FAE channels.

What does the image look like if you upload to a PC and view there?

Is the lens obstructed, with tape, or something?

Issues with voltages and clocks?

http://lxr.free-electrons.com/source/drivers/media/video/ov2640.c?v=2.6.39

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