(09-22-2016, 02:59 AM)MobileFusion Wrote: 1. I am going to buy a LCD screen in the next few weeks, but want to know is there is any operating system which would allow me to run dual screen one HDMI connected to the port and also the lcd?
The basic support for this is available in all Allwinner tablet SoCs (the A series A64 is part of) since day one. Back in those days you configured the display settings in proprietary fex files, now in so called device tree files. Principles are the same. Adding to the link above just two more links:
The second one should give the idea that basic support is easy, getting a combination to work in a reasonable manner is another thing. A reseller of A20 equipment promised me last year to send a 1024x600 dpi LCD for review (never arrived) and I ordered one with HDMI with the same resolution (which caused some hassles due to being a non-standard resolution) to provide a dual display tutorial. Never happened and unfortunately LeMaker's CEO/CTO from the 2nd link above never got back to me. Fortuntely (for me) I almost all the time use Allwinner devices headless anyway.
That being said I would assume that those guys currently bringing Android 7.0 to Pine64 will come up first with working settings (they're doing an amazing job).
Talking about that 1024x600 HDMI display reminds me of some Armbian users reporting getting non-standard HDMI resolutions working flawlessly by tweaking fex files and use the fb0_width/fb0_height parameters on H3 boards. Since HDMI driver in BSP kernel for H3 and A64 is pretty similar that would be worth a try here too. Did a quick search, maybe it was this thread: http://forum.armbian.com/index.php/topic...3-devices/
At least there you find a link to the patches we applied to H3 HDMI driver to provide additional real resolutions. Talked to longsleep about that in March or April and suggested to provide an a64disp utility comparable to the h3disp we wrote for H3 devices back then. IIRC he wanted to adjust display resolution only through settings in uEnvt.txt and refrained from adding additional resolutions. But it should be easy to add the few more native resolutions Armbian added for H3 to BSP kernel sources for A64 also (maybe someone wants to poke ayufan -- I don't think longsleep changed much of his mind regarding display output, he's using Pine64 headless as most if not all linux-sunxi devs).
With H3 it looks currently like this regarding available HDMI resolutions (all it needs is a dev looking in Armbian's github repo and add the stuff the longsleep's kernel):
root@orangepione:~# /usr/local/bin/h3disp
Usage: h3disp [-h/-H] -m [video mode] [-d] [-c [0-2]]
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This is a tool to set the display resolution of your Orange
Pi by patching script.bin.
In case you use an HDMI-to-DVI converter please use the -d switch.
The resolution can be set using the -m switch. The following resolutions
are currently supported:
480i use "-m 480i" or "-m 0"
576i use "-m 576i" or "-m 1"
480p use "-m 480p" or "-m 2"
576p use "-m 576p" or "-m 3"
720p50 use "-m 720p50" or "-m 4"
720p60 use "-m 720p60" or "-m 5"
1080i50 use "-m 1080i50" or "-m 6"
1080i60 use "-m 1080i60" or "-m 7"
1080p24 use "-m 1080p24" or "-m 8"
1080p50 use "-m 1080p50" or "-m 9"
1080p60 use "-m 1080p60" or "-m 10"
1080p25 use "-m 1080p25" or "-m 11"
1080p30 use "-m 1080p30" or "-m 12"
1080p24_3d use "-m 1080p24_3d" or "-m 13"
720p50_3d use "-m 720p50_3d" or "-m 14"
720p60_3d use "-m 720p60_3d" or "-m 15"
1080p24_3d use "-m 1080p24_3d" or "-m 23"
720p50_3d use "-m 720p50_3d" or "-m 24"
720p60_3d use "-m 720p60_3d" or "-m 25"
1080p25 use "-m 1080p25" or "-m 26"
1080p30 use "-m 1080p30" or "-m 27"
4kp30 use "-m 4kp30" or "-m 28"
4kp25 use "-m 4kp25" or "-m 29"
800x480 use "-m 800x480" or "-m 31"
1024x768 use "-m 1024x768" or "-m 32"
1280x1024 use "-m 1280x1024" or "-m 33"
1360x768 use "-m 1360x768" or "-m 34"
1440x900 use "-m 1440x900" or "-m 35"
1680x1050 use "-m 1680x1050" or "-m 36"
Two examples:
'h3disp -m 1080p60 -d' (1920x1080@60Hz DVI)
'h3disp -m 720i' (1280x720@30Hz HDMI)
You can also specify the colour-range for your HDMI-display with the -c switch.
The following values for -c are currently supported:
0 -- RGB range 16-255 (Default, use "-c 0")
1 -- RGB range 0-255 (Full range, use "-c 1")
2 -- RGB range 16-235 (Limited video, "-c 2")
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