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1  Screen Tablet malarky / Build Logs / Re: Unneeded-IQ on: June 23, 2017, 09:30:44 PM
I looked at monitor documentation once again. Schematics are for main PCB. This board have analog RGB input only.
There are also second PCB called power board and contain input connectors. If DVI->VGA converter exist, there must be chip for that job. If You cannot found converter chip (min. 20 pins) on power board, this monitor have only DVI-A input.

I'm 100% sure that dimming are realized by PWM output. No one use DAC for analog output. There are only two options: PWM or analog via PWM + resistor + capacitor.
Look at PDF, page 38, top left corner. There are a lot of signals. Somewhere in the middle You can found DIM-ADJ (7) signal. It's connected to two resistors and capacitor.
IMHO You should use DIY analog->PWM converter. Yes, You can get PWM signal by removing capacitor or by connecting directly to chip (left side od R61 ? ). But there are second problem, PWM frequency. LED driver have limited frequency capacity (often above 100hz, rarely above 1khz). On the other hand monitor chip can easily produce PWM signal with range 4khz - 45khz, depend on selected options.
2  Screen Tablet malarky / Build Logs / Re: Unneeded-IQ on: June 22, 2017, 06:30:00 PM
DVI input:
I checked schematic and cannot found digital input. Looks like main electronic board have only VGA input. I'm not sure whet to say about DVI->VGA converter but I'm sure that it doesn't exist on schematic.

Inverter voltages:
Most CCFL drivers works from 3.3V to 12V. If higher supply voltage is essential, controller may be powered from "enable" line or from main input through resistor and zener (simple voltage stabilizer). First solution is common in laptop designs. In Your case I'm sure that 24V goes only to CCFL transformer and power transistors. 5V goes to driver chip.

Inverter pinout:
look at page 40 (of 41). Inverter need single 5V line. Second one are PWM  Cool
3  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 17, 2017, 06:43:47 PM
Real aluminium tape may cause short circuit and destroy Wacom. I prefer to use different type of tape especially "duck tape" - plastic thing but reinforced.

Front cover have two aspects. First is base material. Glass may be fragile but 2mm layer should be enough for drawing. Plexi are elastic and may bend enough to put pressure to LCD surface but it's easier to cut. 3mm may be enough but I'm not sure. Second thing are just top layer. This layer determines scratch resistance, dirt resistance and friction for pen.
I recommend You to use glass and put protective sticker on top - to reduce pen friction. But again I have only experience based on two tablet-PC screens and few things that I try to put on top of it to cover deep scratches. Based on my experience, scratched surface of tablet screen are the best thing I can found. Bare glass and few plastic things have much higher friction than original tablet surface. So You need to test it all on Your own.
4  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 17, 2017, 04:36:17 PM
I looked one more time at Your photos and noticed that You have strange type of screen.
Normal screen are designed to have small frame but great thickness. That type have PCB folded behind screen.
You have different type of screen designed to be thin but much bigger than active area. You already have PCB located at side of screen and not need to straight the flexible connectors.
I not have experience with that type of screen and cannot help You this time. Sorry.

LCD panel doesn't generate as much heat as You think. That amount of heat cannot burn electronic components inside screen or tablet. Yes You can stack screen on top of Wacom and don't worry about Wacom. There are only two components extra sensitive to heat: liquid crystals inside display and LEDs.
LEDs have designed live time about 30k hours at 30*C (data for regular LED, backlight strip may have different parameters) but live time will drop significantly as temperature increases. To reduce temperature You can keep part of frame near backlight strip or reduce backlight power by PWM dimming (if supported by HDMI converter).
Liquid crystals will refuse to work above certain temperature. As result image will disappear, but reappear when you cooled the screen. If You see that effect at edge of LCD - You almost killed LED backlight.
5  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 17, 2017, 09:57:42 AM
So Wacom works. That's great.
1mm plexi is 1mm wasted space. You need to add 2-3mm top layer (glass/plexi) and let say 1mm gap between LCD and top layer. If Wacom works with extra few mm then You can keep 1mm plexi. If Wacom not work because of distance You need to reduce thickness and probably replace 1mm plexi with something thinner. Hope You understand.

I can't show You the process of disassembling LCD panel. I can only search for that on YT and link You video.
Here You can seen black tape around LCD and how to remove it: https://www.youtube.com/watch?v=DKokN0h94UI
Here how to deal with latches connecting metal and plastic: https://www.youtube.com/watch?v=lrN3E-TIrLU
In both cases LCD projector need to keep only glass part and flex connections. You need to keep backlight unit and plastic frame too.
6  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 16, 2017, 10:45:33 PM
Oh, You have eDP interface. That changes a lot (no LVDS). LCD and controller should work. I cannot see cable that fits both LCD and converter. Hope You have it too.

First stack LCD on Wacom and test if it working. Pen should working without problems when LCD is OFF. When LCD is ON there shouldn't be much jitter in center of screen. Metal should affect Wacom only at edges and corners. If You have problems at center too - You may need to swap LCD screen to different model.

How to remove metal: You need to remove whole black tape and few white pieces from screen. Then unscrew PCB (green part in panel) and try to remove metal without damaging flexible connectors. Metal should be held in place by plastic latches, sometimes glue.

Without metal, bottom part of screen will contain only: PCB, LED strip, white sheet (light reflecting material) and plastic frame.
You need to insulate PCB and LED strip from contact with Wacom. 1mm plexi or kapton tape are great decision. 2-3 layers of adhesive plastic tape are OK.
Other components (most of screen) are already made of plastic thus not need extra insulation.

P.S. Part of metal frame may act as heatsink for LED strip. You should check temperature with and without metal. Overheated LEDs will burn quickly.
7  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 16, 2017, 03:09:03 PM
For VIDEO to LVDS converter (for LCD panel) I recommend TSUMv29 or TSUMv59 or cheap VGA-only converters like this: >Aliexpress<.
Main difference between TSUMv chips are:
- old v29 - resolution selected via jumpers or uploaded via VGA connector by seller.
- new v29 - USB for firmware update (each file for each resolution).
- v39 - same as new v29 but support music and photos from USB.
- v59 - same as v39 but also can play movies.
- v56 - newest alternative for discontinued v59, should work the same way as older one.

Main question: what is Your LCD model and do You have anything more for panel? For example LED backlight should work with internal driver, for CCFL backlight You need external driver saved from laptop or bought separately. Number of CCFL tubes matter, driver for 2 tubes won't work with single tube. Next - cable and connectors. It's better to buy special cable (often cost more than 10$) rather than play on Your own and destroy something.

Okay i Will update with the results. Anyway in still really noob at choosing a protector for the actually screen. What screen protector or what i have to buy to put It by the screen and the Pen to not scratch my fragile 15inch panel??
And i dont know how to strip my panel, what this mean?

For short test LCD panel can work without anything protective on top. Pen with good nib shouldn't scratch screen.
For regular usage scratches wasn't a problem. Real problems are: pressure (both from pen and hand) and removing dirt (water can flow into panel frame then corrosion will destroy something). Thus You need to add protective sheet of glass or transparent plastic and some spacing between plastic and LCD because plastic (plexi/PMMA/lexan/...) will bend when pressed.
Plus, please carefully select material. Some types have high friction, drawing on that wouldn't be as nice as on other types.

LCD panel are made of 2-layer glass (with polarizer, color filters, ...), light source (CCFL/LED strip), backlight diffuser, sheets of diffusers/lenses/..., electronic board (with connector for signal input), drivers mounted on flat flex and metal frame.
Because Wacom works with EMR (electromagnetic) technology, electronic board and metal frame will block signal or cause interferences (search this forum for jitter). Tablet need to remove that parts but LCD wouldn't work without PCB. Only solution are to remove metal frame (strip panel) and gently twist PCB by 180*. In some cases PCB need extra shielding to reduce jitter but that's not my specialization. I prefer to get screen from TabletPC with integrated digitizer, then add two converters and simple case.

My build - TabletPC screen, converters for digitizer and LCD: http://forum.bongofish.co.uk/index.php?topic=2562.msg21888#msg21888
How to strip LCD monitor, then panel: https://www.youtube.com/watch?v=KrwHgTrxpnk
8  Screen Tablet malarky / Heyaaaalpppp / Re: Laptop screen to wacom cintiqfor drawing on: June 10, 2017, 05:03:29 PM
The pressure sensitivity is defined by the wacom board and pen used (so if you use a screen with digitizer like the one you linked, you will only have the amount of pressure levels that the wacom penabled tech gives you which were 512 levels iirc).
Okay nice to hear this! Smiley
I agree with this. "Artistic" tablets (intuos, cintiq, etc.) have typically 1k or 2k pressure resolution. "Embedded" tablets (digitizer hidden behind laptop/tablet screen, maybe the "signature pad" too) have typically 255 or 511 levels. There are more differences between artistic and embedded tablets.

Im seeing some specs about Intuos 4 and 5 and what i saw is that some of they call about "Active area" .
For example the Intuos 5 medium has a size of 37.9 x 25.1  cm and an Active area of 22.3 x 13.9 cm. I do not understand, this mean when i Will open the tablet to fit my 15.4 screen, i Will found an area of 22.3 x 13.9 to draw, or i can draw on all' the size dimension?
Look at Your monitor. Active area can display image. Screen size are the diagonal of active area, but dimensions include plastic frame around screen. There are two reasons why inactive area are so big. First: it's more comfortable if You have large supporting area - palm rest. Or in reverse, if You use part of tablet as palm rest, You never use it for drawing - active area can be smaller. More about second reason below.

I mean is the Active area size, the same as the Green wacom digitizer that i Will find in the tablet ?? Or the Green electromagnetic digitizer is bigger(like all' size dimension)? Thanks! Smiley So i know what panel to use
PS i found this but as i wrote i dont know If i can use all' the size of the tablet or just the "more Black area" to drawGuardalo su eBay http://www.ebay.co.uk/itm/263013637103
Linked tablet are typical artistic tablet.

EMR tablet are made of two main components (tree if include active battery-less pen). First are electronic components that do the magic, second are antennas that communicate with pen and can determinate it's position.
Embedded tablets have these two separated. You can see thin sheet of plastic with funny grid on it - that are the antennas on flex PCB. Antennas are about the same size as LCD glass. Where are located electronic components? On separated PCB, connected to antennas part. P.S. Do nit separate these two parts. You will
Artistic tablets have only one PCB. Antennas are in the middle, electronic components are located around antennas. That are the second reason why artistic tablets have dimensions mush bigger that active area.
I cannot search photos now. Hope You understand that explanations.
9  Screen Tablet malarky / Heyaaaalpppp / Re: Cintiq 21UX with a Severed Cable - Can We Restore It to Working Order? on: May 13, 2017, 09:44:01 AM
If this monitor really need 7A of current, industrial equipment (disconnected each service inspection) will use proper service margin and have 2-pin connectors with 10A per pin capacity. Proper engineered user manageable equipment should have bigger safety margin, let say 15A - 20A capacity to have good enough performance even after years of playing with it. But better connectors always cost more and are more tough than regular low-current ones.
IMHO someone decide to use standard connector with 7A/pin or 10A/pin current capacity but connect two pins parallel to double current capacity. Next thing, proper power cable will be thicker and harder than two with half size and half capacity.

Next, USB. You should have 4 pins in this order: GND, D+, D-, 5V and I hope that Wacom obey standards. If not, here are simple instruction:
GND is often connected to shielding. Ohm-meter can easily check this.
GND and 5V are often connected to input capacitor located near connector. Also, polarity mark can approve where are 5V and GND.
D+ and D- often are routed to two similar SMD components or single 4-pin/6-pin input filter. If You swap these two wires, funny things may happened but You cannot destroy anything. If You swap wires again and tablet working better, You're in home.

* one exception, sometimes You may found solution with 2, 4, 6, 8 'big' power wires and extra 2 small wires. This are sense wires. PSU can read voltage directly at load and increase output voltage to compensate voltage drop over long cables.
10  Screen Tablet malarky / Build Logs / Re: Fujitsu T5010 - utilize screen from Tablet-PC on: May 09, 2017, 09:50:12 PM
<censored /> yeah! I finally got microUSB plug. Attached it to Pro Micro and everything working well. So, back to durable USB socket reinforced with plywood.
[attachment=1] [attachment=2] [attachment=3] [attachment=4]

Let's finish this project (and start another).
All pieces on back of my screen. Removed white connector from LCD/LVDS cable. Added small prototype PCB for buttons and LEDs. Board for digitizer glued to the plywood.

Pro micro stick behind USB connector. All pieces connected. Extra space will be utilized by potentiometer (attached to one of ADC inputs) as soon as I discover how to recompile WaxBee firmware with adding extra piece of code (the idea: analog -> PWM -> backlight dimming).

And ZOOM view.

Because I have spare output from digitizer (high when detect pen) and doesn't have any driver for NUM/Caps/Scroll/Lock LEDs I decided to wire them together  Grin

Everything tested and working OK. No jitter, as expected. Only small hysteresis, something about 1px.
Screen resolution: 1280 x 800px. Digitizer resolution between 1 and 2 points per pixel.

And that's all. Final photos will be posted at first post of this topic. Any comments are welcome.
11  Screen Tablet malarky / Heyaaaalpppp / Re: Cintiq 21UX with a Severed Cable - Can We Restore It to Working Order? on: May 09, 2017, 09:28:27 PM
Look for "4pin CCTV power", you will found that very similar plugs are used for powering analog CCTV cameras. Some links below.

12  Screen Tablet malarky / Build Logs / Re: Fujitsu T5010 - utilize screen from Tablet-PC on: May 03, 2017, 09:45:23 PM
Sorry about long delay. I need to sell one of my Pro Micros to my friend (ASAP project, even 24h waiting for original board will ruin it). I think that I still have second one, but it's disappear  Angry so extra 40 days of waiting.
One problem solved, few next appear.

Part 3b - finishing mechanical assembly
First, hole to pass cables.
[attachment=2] [attachment=3] [attachment=4] [attachment=5]

Next, quick check if LCD and converter still working. Beware, backlight driver (build-in) need something about 12V.
[attachment=6] [attachment=7] [attachment=8] [attachment=9]
Yep, it's working. Changing language to english are simply, just need to discover pinout for keypad. Backlight driver working when applied +12V (LED sypply) and +3.3V (driver supply) for whole LCD.
- wire laptop buttons to LVDS converter (maybe IR receiver too),
- backlight dimming.

Part 4 - WaxBee converter
I not thrust SMT connectors, especially micro USB. First I decided to solder short wires between board and USB-B socket (call it printer-type USB).
But I lost half day and two 22 ohm resistors on PCB without positive effect. Looks like signal from Atmega32U4 need to past through micro-USB connector, then I can cut cable and pass signal through USB-B adapter and next cable. I will test this solution later. Today I will stay with delicate micro USB socket.
Actually WaxBee have nice place next to LVDS converter. Plywood have few gaps designed to fix USB-B board.

Wiring digitizer.
I have finished small PCB which I used to earlier tests. I should remove it, but 3.3V LDO fits here nicely.
I only use 3 wires: VCC, GND and RX because digitizer should work without any extra command.
This decision was big mistake. Digitizer can run without commands but cannot run with random commands - RX pin floating. As a result, WaxBee perfectly read X/Y position but cannot read buttons and pressure  Angry
Finding cause of the problem was rather funny. As soon as I connect RX pin to VCC, problems disappear. But later I decide to play fair and connect digitizer RX to WaxBee TX via extra 1k resistor (standard 10k resistor are build-in on digitizer board).

Wacom template.
I use standard template, Penenabled ISDV4 to Intuos2 12x18
For my digitizer, max X = 28811, max Y = 18083. Digitizer active area are bigger than LCD active area. I need to trim that, min values too, but that will be done later.

- trim min/max for coordinates for digitizer,
- connect all parts at once and test jetter,
- clean front glass on both sides.
13  Screen Tablet malarky / Heyaaaalpppp / Re: Wacom alternatives on: April 17, 2017, 10:48:32 AM
I know that there exist many alternatives but I remember only Wacom. Small hint for You:

New Wacom tablets and used but still pretty new USB models are expensive.
Try to search for much older serial and ADB models. You can use it with modern PCs if You add WaxBee converter (teensy or adruino micro board with proper software).
P.S. Buy only complete sets with pen, cables and power supply. Spare pen can be more expensive than obsolete but fully working tablet.
14  Screen Tablet malarky / Tablet Conversion to USB / Re: Converting Wacom UD-1212-R from Serial to USB on: March 13, 2017, 10:35:26 PM
1. Pro micro and clones are incompatible with Teensya 2.0 There are two problems: pinout (different pin names, not big deal) and bootloader (arduino bootloader suck). Rest (uC, crystal, USB section) are almost identical.
I tried to program old WaxBee into pro micro. With success. But I need external programmer to do that. More info here: http://forum.bongofish.co.uk/index.php?topic=2556.0
Newer WaxBee version have smaller size thus You can use arduino bootloader that are inside pro micro. Just programming process are different. WaxBee can program teensy or generate hex file. You need manually call AvrDude with specific parameters. That's probably the most important difference.

2. You need working EMR pen. Original Wacom pen will be excellent as long as it working (moisture and time may destroy everything). Replacement pen may working too but I never played with that.
15  Screen Tablet malarky / Build Logs / Re: Ribbitiq - trying not to break everything. on: March 13, 2017, 09:52:36 PM
Well. Diffuser have direction because LEDs are only at one side. If You 'fix' the problem by removing silver tape and glue it on the other side, the diffuser will still spread more light on right side and less on left.

Yes, when You move LED strip, You need to rotate diffuser layer.
What about upper layers? IMO You need to rotate only diffuser section which may contain only 'glass' or 'glass' and single sheet above. You can easy test all layers. If layer have different structure/density at different regions it's part of diffuser. If layer have the same structure at any point, it may be lens or something similar. You not need to rotate that.
And please pay attention to layers order and top side. If You mess with that, You will never found the right order.

BTW, why You need to rotate backlight and all optical layers? IMO You can rotate LCD glass without moving frame and backlight, then rotate whole module.
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