Mark Adams a écrit : >>* the image on the VGA monitor lacks a few pixel on the right (approx >>6-7 pixel columns missing): CRTC registers to be adjusted ? >>* the image on the TV lacks even more pixels on the right. I had to >>cheat with GH_ACTIVE, with 773 instead of 720 to be able to get enough >>of the image on the visible area > > On my machine, the output is perfect -- I've checked the timing on a scope. > There could be more differences between the VT1622 and the VT1622A or there > may be something else wrong. Note that you should _not_ be able to see all > 720 pixels: the analogue active line of a PAL TV picture is 702 clocks of 27 > MHz so 9 pixels should be hidden at either end. If you can see all 720 > pixels, the active line is either extending into the line blanking period or > there is a horizontal squeeze.
I also read http://www.tvforum.co.uk/forum/viewtopic.php?p=193549 (last post), with similar information, detailled differently. I just expected to see the whole 720 lines at a time, with a little overscan. Now I know that in fact there is no such 720, but better 702 pixels per line. My 720x576 main test image should then not show the same part on top/bottom and left/right : the corner white circles are hidden on the left/right edges. I just expected them to just fit at the left/right visible part of the image. I should then tune with 702x576 (not 720) test images. This also explains why some DVB channels have some kind of little right/left black bars : these are the 9 non-fitting pixels at each side. >>* HSCALE_FAC is not 0, ie. there is an horizontal (down-)scaling clearly >>visible when viewing the moire_2x2.png test image. Could this be the >>27MHz vs. 28Mhz dotclock effect ? 27MHz should give a wider image than >>28MHz, that I have to compensate using HSCALE_FAC, which is not perfect. > > I don't understand this. I have HSCALE_FAC = 0 and there is no pattening on > your moire test image. If I set HSCALE_FAC to your value, I see extensive > banding. > Perhaps now you've got it working, you might want to try the original code > I sent with just the #define VT1622A changed and see how that turns out? I'll retest and tune more, after understanding that. >>Here is the result of the "D" command in the vt1622 program: > > Here's mine if it's any help: I'll compare. Thanks for all. -- NH _______________________________________________ directfb-users mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-users
