I've experienced some troubles with ADV7842 HDMI background measurements on my own product. I've reproduced the problem on a ADV7619/ADV7511 evaluation board with AVES 2.05.
In fact when I connect a 1080i signal (50 Hz or 60 Hz) on the non active HDMI input, background measures do not lock all the times (BG_PARAM_LOCK stay at 0).
To reproduce that I have done :
- Connect a blue-ray reader on HDMI Port A that outputs 1080i 50Hz
- Execute script ":PortA 720p,1080i,Any CSPace In,24bit YCrCb444 from ADV761X thru HDMI Out 24bit YCbCr FS VIC,4,5,19,20:"
- The output TV displayed successfully the content and detect it as 1080i 50 Hz
- I unplug the cable from HDMI A and connect it to HDMI B ==> A blue screen is displayed on TV (free run enable)
- I refresh the background measures by set BG_MEAS_REQ to 1
- I read BG_PARAM_LOCK several times manually
- Sometimes it is set to 1 with correct measures for a 1080i 50Hz input signal and sometimes it stays to 0
I've done the same experiment with 576i (50Hz), 720p (50Hz and 60Hz) and 1080p (50hz and 60hz) without problems with background measures.