AnsweredAssumed Answered

ADV7842, fast switch to composite from HDMI or RGB

Question asked by usaghi on Sep 18, 2012
Latest reply on Sep 19, 2012 by DaveD



Our customer is asking a question, is there any way to prompt to display composite(SDP) input, switched from HDMI and RGB. Now it takes around 20 seconds til gets normal picture. The symptom are as follows.


1) Soon after switching to composite input, misaligned picture can be observed.

2) After (1), looks to be synchronised but in black and white, as shown in attached cvbs_01.jpg

3) After (2), gain adjusted in color ?, as shown in attached cvbs_02.jpg

4) After (3), normal picture.


Once finished to show normal picture after above adjustment(?), it is continued to work well until power off, however when changing input source device, sometimes above steps may be recurred.

The customer is using register setting which is same as ADV7842 EVB, but invalidate Frame TBC and 3D Comb (SlaveAdrs 0x90, SubAdrs 0x12, 0x00), because their board does not have external memory.


Any advice, comments to improve/abbreviate duration time to display composite input, would be very much appreciated.


Best Regards,