5 Inch Eyoyo Component Screen

Discussion in 'Screens' started by Stitches, Feb 23, 2018.

  1. Stitches 2 and a Half Dollarydoos Staff Member . . .

    Joined:
    Feb 5, 2017
    Messages:
    930
    Likes Received:
    890
    Location:
    Australia
    Portables:
    6
    So there's this little 5 inch screen you can find on ebay by a company named "Eyoyo". This screen accepts component in natively, which is dope. I put one in my AtarWii Liinx and it's so good. It has a few quirks to it that can make it hard to work with blind, though. So since I've already done the work and mapped everything out, I'm making this thread so you beautiful people won't have to sit around pulling your hair out for 12 assorted hours like I did to get it working properly.

    To start with, here are some pictures of the exterior of the screen before opening it up:
    20180223_120603.jpg

    20180223_120726.jpg

    20180223_120619.jpg

    The case is made of black painted steel, which is very sturdy and decent to look at from the front. The back is kinda meh, but all ports are easily accessible. From left to right we have:
    1. A 12v DC in barrel jack
    2. A micro USB port for running it on 5v (did I mention that this beautiful thing takes 5v natively too?)
    3. An HDMI port which doesn't work well according to reviews
    4. A VGA port that takes both VGA AND YPbPr component video
    5. A 3.5mm jack that takes composite video and L+R audio (The Eyoyo has an onboard 1W stereo audio amp)
    6. A useless pain-in-the-ass to remove RF coaxial port that I haven't tested the function of and don't ever plan to.
    7. And above them all, the tacts for the controls. Now, the controls are the first quirk about this screen. The bottom button is a useless power switch, above it is the Source button, above that is -, then Menu, then +. When not in the OSD, + and - control the volume of the onboard audio amp, but you have to hit Menu to make the on screen volume bar go away after changing it. Hitting Menu normally will open the OSD, which can be navigated by pressing Source to scroll down the options, using + and - to select options and adjust sliders. Pressing Menu will move you back one step in the OSD and eventually close it. So you need all 4 non-power buttons to actually use the menu at all. Outside of the OSD, source acts like a Source button should. The order of input modes goes : AV > BNC(coaxial RF) > VGA > HDMI > YPbPr > AV. VGA and YPbPr will freeze for a short while before showing the blue screen if there is no input to those channels, so don't worry about the screen seemingly dying on Source change.
    A good variety of inputs, but we're here for two specific inputs: 5v and VGA for component video. Taking out the side screws allows the screen bezel to slide off, them a bit of prodding the ports will slide the driver board out. It's a snug fit due to the 4 large screw posts that you can see here marked in red:
    20180223_121719-2.jpg
    These things are a bastard to remove without damaging anything. It's hot air and pliers or dremel and pliers, no third option. BE VERY CAREFUL when removing the screw posts. The bottom right one is next to a via on the underside for the screen controls, and if you nick it like I did then you'll have to run a wire like my blue one in the next picture to reconnect the line. Same with the coaxial port, just a pain to remove, although you could carefully cut off that corner of the board safely. A few people have reported problems in their 3.3v lines after removing the screw posts, so be sure to check yours after removal, and again, be very careful when removing these posts. With everything removed the board looks like this:
    20180127_200855-2.jpg
    It's the same dimensions as the LCD panel, so let's talk about how to run this in a portable. The components circled in yellow on the left can be removed if you're going to run the screen on 5v. 5v can be supplied to the points squared in purple, but if you take off the diodes then only the centre pad will work. The orange squares indicate the 3.3v line, which can be used to power small components like a GC+ or IR LEDS. If you want to, you can desolder the linear reg and supply 3.3v from custom regs straight to the pads to run the screen, but you must still supply a small amount of 5v to the 5v line because the backlight won't work properly on 3.3v.

    Just above the top left of the RTD chip are the onboard audio amp's input traces. Normally you would input audio through the 3.5mm AV jack pads, but those inputs are disabled in component mode. So you have to supply audio to the vias/caps. Above the 3.3v linear reg are the outputs for the onboard amp squared in light blue, which have a silk screen box next to them indicating R+ R- L+ L-.

    And finally, the reason we're all here: Component video in, bottom middle marked in their respective colours with black below them for GND pins. This is where the main quirk manifests, because the input pins for component video are in the wrong order. From right to left with this orientation of a VGA port, the first three pins on the top line are supposed to be Red Green Blue, but they aren't. It goes Green Blue Red. I don't know if this is a mistake on their part, or intended, but it took me a long time to figure this out.

    In order to test the screen without having to first open it and solder to the VGA pins, you'll need a component to VGA adapter like this one:
    [​IMG]
    They're cheap on ebay, so pick one up with the Eyoyo if you decide to get one. .
    20180223_120835.jpg
    The odd input arrangement.
    20180223_121310.jpg
    All plugged in and ready to test. I'm using 5v from a phone charger because I misplaced my 12v supply.
    20180223_121301.jpg
    Wonderful. And since it's not HDMI, there are no black bars on the top/bottom of the screen. Widescreen mode uses nearly the whole screen, and 4:3 looks just as good (I prefer it actually).

    I hope this shit excuse for a doc thread is of help to anyone who wants easy 480p. I'll also include this link to the ebay listing where I bought my screens: https://www.ebay.com/itm/232529903093 . There are more listings like it, just search for ' eyoyo 5" ' on ebay and heaps should show up. They're a bit more expensive than the usual AV/VGA/HDMI only screens, but native component so ¯\_(ツ)_/¯

    Happy building! If you buy one of these and make any discoveries, or just have questions, feel free to post them here.
     
    Last edited: Mar 5, 2018
  2. BocuD . .

    Joined:
    Jul 21, 2016
    Messages:
    306
    Likes Received:
    281
    Location:
    The Netherlands
    Portables:
    2
    TLDR: I fckd up my lcd and by probing around trying to fix it I found out how to control brightness.
    Long version:
    So.. I got the lcd a few weeks ago and today I disassembled it. I had problems removing the screw posts (like @Stitches mentioned can be hard) and accidentally cut a trace. I didn't notice this until hooking it back up, however. I noticed the backlight wasn't working anymore, so I asked for help in the discord. @GingerOfOz mentioned that I cut a trace connecting 5v to the backlight regulation circuitry. Once I noticed this was the case I started probing around on the screen when I suddenly noticed that when I connected the multimeter pins between a certain pin and ground that the backlight suddenly came on. So I looked up the datasheet for the backlight voltage regulator, and found out it is the same one I am using in my custom driver board im designing for the RTD2660H, the main driver IC used in the eyoyo screen and many others. The datasheet mentioned some interesting information about the pin I measured with my multimeter probes to gnd. It is the EN (enable) pin of the regulator, and can be controlled by either supplying the input voltage or a pwn signal to it. Simply supplying the input voltage (what is done on the eyoyo screen) makes it default to supplying the maximum amount of current it can according to RSET (resistor used to set the maximum current the regulator "regulates") but when supplying the EN pin with a pwm signal, the duty cycle determines what percentage of the maximum current is regulated. So I tested this by hooking up the lcd driver to an Arduino to try and control the brightness (something the lcd normally doesn't allow) and it immediately worked. Here's a "demo" of it working:


    So, how do I do this myself?
    Step one

    Cut the trace trace like the red line suggests
    This disconnects the 5v power from the enable pin, forcing it to use the signal we give it instead of defaulting to maximum current.
    20180223_121719-2.jpg
    20180223_121719-2-3.jpg
    Step two
    Get your Arduino or other microcontroller ready, and hook it up the pin highlighted in blue with a pin which can be controlled by PWM on the Arduino or other microcontroller.
    Make sure the PWM signal generated by the microcontroller is 5v, and that you power the lcd off of the same 5v line as the microcontroller
    Step three:
    Use some coding magic to control the backlight brightness
    On an Arduino this is quite easy. You can just use AnalogWrite(pin, value); In the main loop function and change the value between 0 and 255 for 0 and 100% brightness respectively. Good luck with further portablizing!
     
    Stitches likes this.

Share This Page

Loading...