title: STM32H7 DCMI with BT.656
body: <p>I am currently making a system using digital camera, my camera resolution is 384x288 4:2:2 YCbCr. My camera works on BT.656 with embedded sync (without hardware sync).
  I configured STM32 DCMI with embedded sync and it didn't work. Then I started to debug it and found some weird STM32 DCMI issue:</p>
  
  <p>STM32 DCMI embedded for BT.656 is inverted. </p>
  
  <p>STM32 DCMI document (out of ST's 
  <a href="https://www.st.com/resource/en/application_note/dm00373474-digital-camera-interface-dcmi-on-stm32-mcus-stmicroelectronics.pdf" rel="nofollow noreferrer">AN5020</a>):
  <a href="https://i.stack.imgur.com/p3Mij.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/p3Mij.png" alt="enter image description here"></a></p>
  
  <p>BT.656 Protocol (from 
  <a href="https://techdocs.altium.com/display/FPGA/ITU-R+BT.656+Protocol" rel="nofollow noreferrer">here</a>):
  <a href="https://i.stack.imgur.com/PA85X.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PA85X.png" alt="enter image description here"></a></p>
  
  <p>I have 2 questions:</p>
  
  <ol>
  <li>Has anyone been able to make BT.656 work on STM32H7 or any STF32FXX?</li>
  <li>BT.656 resolution for PAL is 720x576 but my camera is 384x288.
  What is the format of the camera? 
  Or: How can I understand how many lines are used?</li>
  </ol>