s_cornford
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sat Jan 30, 2016 6:56 pm

Yep, I put those three lines in the configure.txt and changed the advanced options, which added another two lines at the bottom.

I tried two different cables, both of which I know worked on other gear, so it's not that. Last night I ordered one of those pre-assembled vga shields from deal extreme, just so that I can see if it is the soldering, but I doubt it.

I'll try the whole process from the top again next time I'm at my desk.

edit: forgot to say that I installed Wheezy because I read somewhere that it had omxplayer already as part of the OS - but it occurs to me now that that might have been a dated post, and that omx is part of all versions since.

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AndyD
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sun Jan 31, 2016 11:18 am

Sorry, no idea. I can't think of anything. When you said "and changed the advanced options, which added another two lines at the bottom." what are the extra two lines?

postnoctum
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sat Feb 20, 2016 5:23 pm

Does anyone have an image of this working on a clean Raspbian or NOOBS install? I'm trying to get this set up on a fresh install anyways and i've spent a couple hours messing with different HOWTOs to no avail....

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AndyD
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sun Feb 21, 2016 2:48 am

@postnoctum are you sure your VGA 666 adapter is wired up correctly? It really should just work if you follow the instructions in the first post of this thread.

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mahjongg
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sun Feb 21, 2016 2:35 pm

.oKINGYo. wrote:Good news!....sort of.... I have an image on my screen of the desktop but is very off colour, quite dark and the blue and red seem to have taken over a bit...but its WORKING :D is there a PAL/NTSC issue? doubtful but ill ask the question anyway.
this is indicative of either soldering errors, or using the wrong resistors in the wrong place.
For example if your soldering looks like this (open picture in new window with a right click on the picture, to enlarge the picture):
Image
Then I'm sorry to say you did a bad job, I see several bad solder joints in this picture especially the middle of the lower row of the GPIO header has many bad joints (insufficient wetting). They need re-soldering with more heat and more flux, the solder should rise up to the pin like mount Fuji, not as a ball on top of the pin, not flown out onto the pad, you should not see any part of the copper around the solder holes.

Here is a picture showing bad and good solder joints:

Image

from adafruit excellent tutorial, here: https://learn.adafruit.com/adafruit-gui ... n-problems

cpv
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Feb 26, 2016 11:56 pm

So, I just bought this board and it works great, I was just wondering if this works with the Model 2 ?

martenjacobs
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Wed Mar 09, 2016 2:57 pm

cpv wrote:So, I just bought this board and it works great, I was just wondering if this works with the Model 2 ?
I can confirm it works with Model 2

tvjon
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Tue Mar 15, 2016 11:42 pm

On RPi3, the only way I've found to enable the vga666 interface again is by entering another line in

/boot/config.txt:

dtoverlay=pi3-disable-bt-overlay

which currently means no internal bluetooth interface available whilst using vga.

Wifi is ok though.

EDIT:

no longer necessary with updated firmware & Linux, & bluetooth now works whilst VGA666 is enabled :)

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mikerr
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Tue Apr 19, 2016 7:03 pm

On the pi3 I use this config.txt on raspbian Jessie (no other config)

Code: Select all

dtoverlay=vga666
enable_dpi_lcd=1
display_default_lcd=1

dpi_group=2
dpi_mode=16

dtparam=spi=off
dtparam=i2c_arm=off

dtoverlay=pi3-disable-bt-overlay
without the last line I get a blue tint (bluetooth - haha) and unstable screen:
Image
even with updating jessie and rpi-update - I don't need bluetooth anyway.
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tvjon
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Thu Apr 21, 2016 7:10 am

Interesting.

Any reason you use

dpi_mode=16

rather than 82?

I get a vertically squashed picture using 16.

What's the output from:

raspi-gpio get?

pi@j1 ~ $ raspi-gpio get
BANK0 (GPIO 0 to 27):
GPIO 00: level=0 fsel=6 alt=2 func=PCLK
GPIO 01: level=0 fsel=6 alt=2 func=DE
GPIO 02: level=0 fsel=6 alt=2 func=LCD_VSYNC
GPIO 03: level=0 fsel=6 alt=2 func=LCD_HSYNC
GPIO 04: level=0 fsel=6 alt=2 func=DPI_D0
GPIO 05: level=0 fsel=6 alt=2 func=DPI_D1
GPIO 06: level=0 fsel=6 alt=2 func=DPI_D2
GPIO 07: level=0 fsel=6 alt=2 func=DPI_D3
GPIO 08: level=0 fsel=6 alt=2 func=DPI_D4
GPIO 09: level=0 fsel=6 alt=2 func=DPI_D5
GPIO 10: level=0 fsel=6 alt=2 func=DPI_D6
GPIO 11: level=0 fsel=6 alt=2 func=DPI_D7
GPIO 12: level=0 fsel=6 alt=2 func=DPI_D8
GPIO 13: level=0 fsel=6 alt=2 func=DPI_D9
GPIO 14: level=0 fsel=6 alt=2 func=DPI_D10
GPIO 15: level=0 fsel=6 alt=2 func=DPI_D11
GPIO 16: level=0 fsel=6 alt=2 func=DPI_D12
GPIO 17: level=0 fsel=6 alt=2 func=DPI_D13
GPIO 18: level=0 fsel=6 alt=2 func=DPI_D14
GPIO 19: level=0 fsel=6 alt=2 func=DPI_D15
GPIO 20: level=0 fsel=6 alt=2 func=DPI_D16
GPIO 21: level=0 fsel=6 alt=2 func=DPI_D17
GPIO 22: level=0 fsel=6 alt=2 func=DPI_D18
GPIO 23: level=0 fsel=6 alt=2 func=DPI_D19
GPIO 24: level=0 fsel=6 alt=2 func=DPI_D20
GPIO 25: level=0 fsel=6 alt=2 func=DPI_D21
GPIO 26: level=0 fsel=6 alt=2 func=DPI_D22
GPIO 27: level=0 fsel=6 alt=2 func=DPI_D23
BANK1 (GPIO 28 to 45):
GPIO 28: level=0 fsel=0 alt= func=INPUT
GPIO 29: level=1 fsel=0 alt= func=INPUT
GPIO 30: level=0 fsel=0 alt= func=INPUT
GPIO 31: level=0 fsel=0 alt= func=INPUT
GPIO 32: level=1 fsel=7 alt=3 func=TXD0
GPIO 33: level=1 fsel=7 alt=3 func=RXD0
GPIO 34: level=0 fsel=7 alt=3 func=SD1_CLK
GPIO 35: level=1 fsel=7 alt=3 func=SD1_CMD
GPIO 36: level=1 fsel=7 alt=3 func=SD1_DAT0
GPIO 37: level=1 fsel=7 alt=3 func=SD1_DAT1
GPIO 38: level=1 fsel=7 alt=3 func=SD1_DAT2
GPIO 39: level=1 fsel=7 alt=3 func=SD1_DAT3
GPIO 40: level=0 fsel=4 alt=0 func=PWM0
GPIO 41: level=0 fsel=4 alt=0 func=PWM1
GPIO 42: level=1 fsel=4 alt=0 func=GPCLK1
GPIO 43: level=1 fsel=4 alt=0 func=GPCLK2
GPIO 44: level=1 fsel=0 alt= func=INPUT
GPIO 45: level=1 fsel=0 alt= func=INPUT
BANK2 (GPIO 46 to 53):
GPIO 46: level=1 fsel=0 alt= func=INPUT
GPIO 47: level=1 fsel=0 alt= func=INPUT
GPIO 48: level=0 fsel=4 alt=0 func=SD0_CLK
GPIO 49: level=1 fsel=4 alt=0 func=SD0_CMD
GPIO 50: level=1 fsel=4 alt=0 func=SD0_DAT0
GPIO 51: level=1 fsel=4 alt=0 func=SD0_DAT1
GPIO 52: level=1 fsel=4 alt=0 func=SD0_DAT2
GPIO 53: level=1 fsel=4 alt=0 func=SD0_DAT3
pi@j1 ~ $


I'm currently testing:

dtoverlay=dpi24

rather than

dtoverlay=vga666

hence I have 2 additional pins defined for a LCD screen (no effect on vga666)

procount
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Thu Apr 21, 2016 8:48 am

JSingleton wrote:sh: can't access tty; job control turned off
Link

NOOBS doesn't play well with the VGA666.
Because it uses certain GPIO pins, it ends up dumping you at the recovery command shell with the above error (that you can safely ignore).

But if you want to use NOOBS with the VGA666 adaptor, you can use my fork (modified version) of NOOBS called PINN. See my post here
PINN - NOOBS with the extras... https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=142574

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mikerr
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Thu Apr 21, 2016 8:59 am

tvjon wrote:Any reason you use dpi_mode=16 rather than 82?

I get a vertically squashed picture using 16.
It was on a small 4:3 monitor - 1024x768 fit best
What's the output from raspi-gpio get?

Code: Select all

pi@raspberrypi:~ $ raspi-gpio get
BANK0 (GPIO 0 to 27):
  GPIO 00: level=1 fsel=0 alt=  func=INPUT
  GPIO 01: level=1 fsel=0 alt=  func=INPUT
  GPIO 02: level=0 fsel=6 alt=2 func=LCD_VSYNC
  GPIO 03: level=0 fsel=6 alt=2 func=LCD_HSYNC
  GPIO 04: level=1 fsel=6 alt=2 func=DPI_D0
  GPIO 05: level=0 fsel=6 alt=2 func=DPI_D1
  GPIO 06: level=1 fsel=6 alt=2 func=DPI_D2
  GPIO 07: level=0 fsel=6 alt=2 func=DPI_D3
  GPIO 08: level=1 fsel=6 alt=2 func=DPI_D4
  GPIO 09: level=0 fsel=6 alt=2 func=DPI_D5
  GPIO 10: level=0 fsel=6 alt=2 func=DPI_D6
  GPIO 11: level=0 fsel=6 alt=2 func=DPI_D7
  GPIO 12: level=0 fsel=6 alt=2 func=DPI_D8
  GPIO 13: level=0 fsel=6 alt=2 func=DPI_D9
  GPIO 14: level=0 fsel=6 alt=2 func=DPI_D10
  GPIO 15: level=1 fsel=6 alt=2 func=DPI_D11
  GPIO 16: level=1 fsel=6 alt=2 func=DPI_D12
  GPIO 17: level=0 fsel=6 alt=2 func=DPI_D13
  GPIO 18: level=1 fsel=6 alt=2 func=DPI_D14
  GPIO 19: level=0 fsel=6 alt=2 func=DPI_D15
  GPIO 20: level=0 fsel=6 alt=2 func=DPI_D16
  GPIO 21: level=1 fsel=6 alt=2 func=DPI_D17
  GPIO 22: level=0 fsel=0 alt=  func=INPUT
  GPIO 23: level=0 fsel=0 alt=  func=INPUT
  GPIO 24: level=0 fsel=0 alt=  func=INPUT
  GPIO 25: level=0 fsel=0 alt=  func=INPUT
  GPIO 26: level=0 fsel=0 alt=  func=INPUT
  GPIO 27: level=0 fsel=0 alt=  func=INPUT
BANK1 (GPIO 28 to 45):
  GPIO 28: level=0 fsel=0 alt=  func=INPUT
  GPIO 29: level=1 fsel=0 alt=  func=INPUT
  GPIO 30: level=0 fsel=0 alt=  func=INPUT
  GPIO 31: level=0 fsel=0 alt=  func=INPUT
  GPIO 32: level=1 fsel=7 alt=3 func=TXD0
  GPIO 33: level=1 fsel=7 alt=3 func=RXD0
  GPIO 34: level=1 fsel=7 alt=3 func=SD1_CLK
  GPIO 35: level=1 fsel=7 alt=3 func=SD1_CMD
  GPIO 36: level=1 fsel=7 alt=3 func=SD1_DAT0
  GPIO 37: level=1 fsel=7 alt=3 func=SD1_DAT1
  GPIO 38: level=1 fsel=7 alt=3 func=SD1_DAT2
  GPIO 39: level=1 fsel=7 alt=3 func=SD1_DAT3
  GPIO 40: level=0 fsel=4 alt=0 func=PWM0
  GPIO 41: level=0 fsel=4 alt=0 func=PWM1
  GPIO 42: level=0 fsel=4 alt=0 func=GPCLK1
  GPIO 43: level=0 fsel=4 alt=0 func=GPCLK2
  GPIO 44: level=1 fsel=0 alt=  func=INPUT
  GPIO 45: level=1 fsel=0 alt=  func=INPUT
BANK2 (GPIO 46 to 53):
  GPIO 46: level=1 fsel=0 alt=  func=INPUT
  GPIO 47: level=1 fsel=0 alt=  func=INPUT
  GPIO 48: level=0 fsel=4 alt=0 func=SD0_CLK
  GPIO 49: level=1 fsel=4 alt=0 func=SD0_CMD
  GPIO 50: level=1 fsel=4 alt=0 func=SD0_DAT0
  GPIO 51: level=1 fsel=4 alt=0 func=SD0_DAT1
  GPIO 52: level=1 fsel=4 alt=0 func=SD0_DAT2
  GPIO 53: level=1 fsel=4 alt=0 func=SD0_DAT3
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rastoma
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Thu May 05, 2016 9:13 pm

Well, after almost giving up on this adapter and getting ready to toss it, I read through this forum and copied/pasted the needed lines for config.txt, which I had already entered, but I typed them, more than once, looking at each character to ensure it was correct.... but after deleting my lines and pasting from some of the posts here, the adapter came to life finally!!!

So thank you all for that.

But I'm only partially thrilled. Like 1-2 others have experienced, I'm getting a bad blue tint on the screen with a little flashing of green lines occasionally that I know is not coming from the monitor itself as I have tested it on a PC and the picture/colors are fine.

I was satisfied with my soldering skills, I have a fair amount of experience. I don't see any joints that could be possible be bad.

All the resistors were marked and grouped with those of the same values so hopefully they were marked correctly.

Now one dumb/silly thing I did, and I don't know why I did it, it was only after I was done did I realize that I soldered the through-hole resistors on the opposite of the board. Since they are through-hold and not surface mount, it shouldn't make a difference would it?

I'm using this on a RPI3 running Incredible PBX. A monitor is not a must have after initial setup since I can do anything needed in SSH, but it was still a fun project to do (though I didn't realize it was a kit and not already assembled when I ordered it).

I would like get it working. Do I need to move the resistors to the other side of the board? I've used a magnafying glass to check the solder joints. The only area I can't check is under the pin header. I used just enough solder on the pins to make fill in the hole and can't believe it was enough to run under the header to short out any of the pins.

I have a second RPI3 I would like to use one of the adapters on as well. Who has the best shipping rate for the US on these? I ordered this first one with some other items to justify the $7+ shipping cost (it was $7.10 for just the adapter or for several other items added on).

I'm new here so excuse me if I am not including something I should be on a post like this.

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mikerr
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri May 06, 2016 8:14 am

But I'm only partially thrilled. Like 1-2 others have experienced, I'm getting a bad blue tint on the screen with a little flashing of green lines occasionally that I know is not coming from the monitor itself as I have tested it on a PC and the picture/colors are fine.
Blu tint and flashes sounds very much like the bluetooth issue I had, fixed by adding this to config.txt:

Code: Select all

dtoverlay=pi3-disable-bt-overlay
Is your firmware fully up to date, and can you test on a different pi (not a pi3) ?
Android app - Raspi Card Imager - download and image SD cards - No PC required !

jamaicaeule
Posts: 2
Joined: Fri Jun 24, 2016 4:04 pm

Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Jun 24, 2016 4:20 pm

I successfully soldered it together and get picture either on HDMI or VGA depending on my config, but I haven't yet been able to get both working at the same time. Am I missing something or is it impossible to drive two desktops at the same time with this adapter?

I saw some things about creating a second framebuffer to extend the desktop to the composite connection, at the cost of fps though.

edit: After reading about that one media player that supports the second screen I hope that some solution to drive two 1080p screens at the same time "the normal way" can be found. 30fps would be more than enough.

jamaicaeule
Posts: 2
Joined: Fri Jun 24, 2016 4:04 pm

Re: Using a Gert VGA 666 adapter - [HOWTO]

Wed Aug 24, 2016 4:16 pm

Sorry about the double post, but I am really interested to be able to do a dual monitor setup, including the desktop environment. I planned to use the raspis with this adapter for some monitoring applications where only one ethernet socket is available but two monitors are required.

Have there been any advances in this? To be honest I feel slightly cheated by the dealers, the many blogposts and even the manual talking about a dual-monitor setup with this adapter.
Double screen
In contrast to the composite video, the DPI interface can be run independent of the HDMI. Thus next
to the HDMI screen, the VGA can be used as ‘second monitor’. The software for that is still under
development but I expect that to arrive in the next two week. Beware that running two screens at
maximum resolution will really eat into your SDRAM bandwidth. In fact it has not tried yet, so it
might not be possible.
Did he overestimate the enthusiasm of the Raspi community? Why is this passage still in the manual if it's not possible? I would never have bought the adapter if I had known the truth about the dual monitor "support" as I have no need for single VGA output. I could have just bought a HDMI->VGA adapter for 6€ if I had needed that...

Just look at this dealer's description: http://shop.queststem.com/product/gert-vga-adapter-666
It is also possible to drive this VGA interface at the same time as the HDMI connection, so a dual / double screen set up is possible.
I doubt that he is intentionally misleading his customers, instead he's probably malinformed.

inb4 "but it is possible!!11!". Yeah, if you edit a program's source code in a non trivial way...

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mikerr
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Sun Aug 28, 2016 6:13 pm

It depends what you want on that second monitor.

What does work is omxplayer playing to VGA666 with a full desktop on the HDMI (or vice versa)

What doesn't is an X desktop on both screens at once. This does work with a USB-VGA adaptor though.
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BMS Doug
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Mon Oct 10, 2016 11:03 pm

mikerr wrote:On the pi3 I use this config.txt on raspbian Jessie (no other config)

Code: Select all

dtoverlay=vga666
enable_dpi_lcd=1
display_default_lcd=1

dpi_group=2
dpi_mode=16

dtparam=spi=off
dtparam=i2c_arm=off

dtoverlay=pi3-disable-bt-overlay
I'm trying to get my vga666 working again as my daughter wants a dedicated monitor (and my mother-in-law was getting rid of her old dell monitor)

I'll try these settings as the monitor is 1024x768 (although this is for her b+ rather than her pi3).
Doug.
Building Management Systems Engineer.

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FTrevorGowen
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Tue Oct 11, 2016 11:56 am

BMS Doug wrote:
mikerr wrote:On the pi3 I use this config.txt on raspbian Jessie (no other config)

Code: Select all

dtoverlay=vga666
enable_dpi_lcd=1
display_default_lcd=1
dpi_group=2
dpi_mode=16
dtparam=spi=off
dtparam=i2c_arm=off
dtoverlay=pi3-disable-bt-overlay
I'm trying to get my vga666 working again as my daughter wants a dedicated monitor (and my mother-in-law was getting rid of her old dell monitor)
I'll try these settings as the monitor is 1024x768 (although this is for her b+ rather than her pi3).
FWIW, and coincidently, that's the resolution of the Dell Monitor I finally got around to getting my VGA666 working on:
http://www.cpmspectrepi.uk/raspberry_pi ... apter.html
(tail of /boot/config.txt shown in the last screenshot. Tested with current Raspbian Jessie Pixel)
Trev.
Usually running Raspbian Jessie on up to 13 Pi's (an A, B1, 2xB2, 2xB+, A+, P2B, 3xP0, P3B, P0W). See: https://www.cpmspectrepi.uk/raspberry_pi/raspiidx.htm

Brian101
Posts: 1
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Oct 28, 2016 2:25 pm

Just got my Gert to work.
are there more resolution options.
i have used the following resolutions

dpi_group=2
dpi_mode=16-9 and 82 was to high

neto10
Posts: 1
Joined: Fri Nov 11, 2016 3:37 pm

Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Nov 11, 2016 4:03 pm

Grettings!

I am currently making a vga888 inspired in vga666 pdf and schematics.

Does the dpi24 overlay gives me access to the pins like tvjon's post and that would be enough to work?
Since the documentation is not actualized, i am facing some questions in this matter. The dt-blob.bin and dts are not working, and i have read about the dtbo structures and overlays to access the vga666, and i have some doubts.

I haven't tested yet in 666 layout, because i dont want to remake the circuit in the breadboard xD. So please give me some advice on this matter.

I will post latter here the 888 working circuit and the final board if i validate this.

PS: Sorry about poor English, i dont use it in my country. xD

bingevader
Posts: 3
Joined: Wed Nov 16, 2016 6:16 pm

Re: Using a Gert VGA 666 adapter - [HOWTO]

Mon Dec 05, 2016 10:10 pm

I'm struggling with mine. :(
I've used all the Pi3 settings.
I've used an ammeter and all resistors are correct.
I get no out put to any display (tried several).
The frustrating thing is that once the settings are altered, I can't revert back to an alternative hdmi display, I have to re-flash the SD card!
Anyone with any other ideas or tests I can carry out on the adapter, I'd really appreciate them!

james-at-lo-tech
Posts: 45
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Thu Dec 08, 2016 9:57 pm

I've released a 24-bit VGA board today - see here.

bingevader
Posts: 3
Joined: Wed Nov 16, 2016 6:16 pm

Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Dec 09, 2016 5:39 pm

That looks very nice James, but I was hoping to get mine working.
Is your kit pre assembled?
The site says it is just the board, so not the resistors or the vga connector?
Is that right?
I'm assuming that's the case at only £3. :)

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Gert van Loo
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Re: Using a Gert VGA 666 adapter - [HOWTO]

Fri Dec 30, 2016 11:34 pm

james-at-lo-tech wrote:I've released a 24-bit VGA board today - see here.
There was a very good reason why the VGA666 uses only 6 bits per channel. This has to do with the precision of the components.
The design uses 1% resistors as they are common available. Thus the resistors for the MS-bit can be off by +/- 1%.
(The MS bit resistor can be off by 320 ohms.) Thus the variation between the R and G and B channels is 2% from that alone.
The LS resistor is 500 Ohm, which is just a bit bigger then the 320 ohm uncertainty value.
An 8 bit resistor network should then be 1/256 or 0.39% accurate. (+/- 0.2%)
With the 6-bits per channel, the colours in the current design already show 'banding' (In some places the colour jumps are clearly visible).
I have not tried but theoretically in an 8-bit design with 1% resistors the LS bits should be ineffective.

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