Video randomly going off

guddler
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Video randomly going off

Unread post by guddler »

Is anyone else seeing this?

I have a Benq 1702A (I think that's what it is) 15Khz capable LCD monitor. It can look out and out lovely when it's set up right. I have it set up using an HDMI to VGA adapter. direct_video=0 (direct_video refuses to work even though I would think the screen could take the resolutions). It has a native resolution of 1280x1024@60Hz. Sadly that is too big for an Amiga RTG desktop at 17" and everything is really small so we have to go to a lower than native resolution.

If I set the mister to 1024x768@60 for the minimig core and the desktop at the same, specifying HV-Integer scaling which of course it doesn't need to use as it's a1:1 to the frame buffer setting then I can leave the mister on for hours on end and it won't bat an eyelid. Dropping to a PAL game isn't bad at all but there is a sizeable border all round and it's offset to one side - this I know about and it's not the issue.

If instead I specify 800x600@60 the PAL programs have much less of a border and they look pretty good but if I just leave the system at the 800x600@60 RTG desktop the screen blanks for a second or two every now and again. Often enough to be unnerving that something might be wrong. But this is a much better resolution.

I initially thought that I might have been pushing the FPGA clocks a bit hard but it's the LOWER resolution that's blanking out on me so I would have thought that the higher resolution would be pushing harder?

Any ideas?
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darksakul
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Re: Video randomly going off

Unread post by darksakul »

The monitor is a 31khz monitor and does not support 15khz.

It's also a older LCD Screen, it only handles one resolution, in this case 1280x1024

Here the manual if you want a closer look
https://www.manualslib.com/manual/15623/Benq-Fp731.html
https://esupportdownload.benq.com/esupp ... 731_EN.pdf


You are best off with a HDMI to VGA Adapter with the following settings
video_mode=4
forced_scandoubler=1

The vga_scaler option will do nothing for you as you are using the HDMI out.

Dropping to PAL mode is always going to add a Border, that just PAL for you.
It is my great regret that we live in an age that is proud of machines that think and suspicious of people who try to.
zakk4223
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Re: Video randomly going off

Unread post by zakk4223 »

Why did you link manuals for the FP731 when the poster probably means the BL702A?
guddler
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Re: Video randomly going off

Unread post by guddler »

I wish this forum sent me notifications when people reply or send me messages - I might not need to accidentally stumble over my own posts via google!!

[EDIT] I've now found and changed the required settings - hopefully I'll know this time if someone replies !

Yes, I mean the BL702A. It absolutely can support 50Hz and even 15Khz, even if the specs on the website don't advertise the fact. I can plug my actual Amigas (A1000, A600 and A1200) into it just fine with a simple 23 pin to 15pin d-sub adapter I made. You just need to go into the service menu (I totally forget how now) and disable the irritating non-optimal mode warning that otherwise comes up all the time. You only need to do that once when you first get the monitor.

Anyway, It still does it I believe, I just haven't been using the mister so much lately.
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