Are SCOMM4 and SCOMM5 required?

SCOMM5 is only required if synchronization of VDATA inputs or outputs is required when using more than one ADV202/212.

In this case, SCOMM5 of each ADV202/212 must be asserted by the host processor to start VDATA input or VDATA output.

SCOMM4 is optional. In encode mode SCOMM4 will assert when the last word is being read out of the CODE FIFO. In decode mode it will stay asserted as long as there is active video present in the Pixel Interface.