interface a camera with STM32F469I-DISC0 when not all DCMI data pins exposed?
Hi everyone,
I'm trying to interface a DVP camera (like OV5640) with the STM32F469I-DISC0 board using the DCMI peripheral in 8-bit parallel mode.
What I have:
- The camera is configured and outputs data correctly via I2C.
- I'm using bare-metal code (no HAL or CubeMX), and SDRAM + USART debug are working.
- DCMI pins are being mapped as per the STM32F469 reference manual.
- I verified that I can access and remap the following DCMI pins:
- D0 – available
- D1 – available
- D2 – available
- D3 – available
- D4 – not available(e.g., PE5)
- D5 – available
- D6 – available
- D7 – available
- HSYNC, VSYNC, PCLK – available
Problem:
- DCMI_D4 is not brought out on any connector** on the DISC0 board. It's internally routed to LCD or unused.
- I checked the board schematic and there’s no easy way to solder to it either.
My questions:
1. Can DCMI work with 7-bit data (skipping D4)? Will DCMI capture still be valid if D4 always reads 0?
2. Is there any known workaround for the missing D4 line (e.g., using a dummy input, or masking D4 at software level)?
3. Has anyone successfully interfaced a camera with this DISC0 board and ignored one DCMI data line?
4. Would you recommend switching to 4-bit mode or dropping down to RGB444 or YUV422 and masking bits?
Additional context:
- My goal is to capture camera frames in RGB565 or YUV format and display/stream/debug from SDRAM.
- I’m okay to accept reduced image quality if 1 bit is lost (e.g., D4 = 0 always), but want to understand if DCMI handles this gracefully or fails.
Thanks in advance for any insights or prior experiences!
Sanjay S K
