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Lighting direction and uses for PC

Discussion in 'Hyperion General' started by Mysta, 15 June 2016.

  1. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    I had a question or two. I made a setup for tv using hdmi split which works great. I used a lightpack though and wanted to go a bit higher def for my PC monitor, as well as go DIY. So I ordered a set of APA102-c that come with the led connector and separate Power connector and I bought a power supply for them. Anyone have any info on going about connecting that to a PC or rpi for processing? Ideally I'd like to use my PC to process colors directly but if I need to output to RPi I will do that too. Just not sure how to connect to the PC.(USB, etc?)

    Also, is there a huge benefit for facing the LED exactly perpendicular to monitor(Outward) vs angle, vs toward the wall? I was hoping to just do outward so I didn't have to cut/rewire the corners but it's no huge issue if it makes a big difference. Another thing is my monitor is curved, so that may change it up a bit.

    For power, since mine has a power input on both ends. Do I need to splice a ground out of the beginning or end and connec to the RPi? Even if I want to use USB to power the pi itself and use the external power supply for LED?(if yes what is the point of this?)

    Thanks!

    PS: Have you seen the RGB headers on ASUS motherboard, curious if they're controllable through an API?https://rog.asus.com/19342015/maxim...-aura-lighting-control-and-rgb-strip-headers/
     
  2. Brindosch

    Brindosch Administrator Administrator

    Messages:
    679
    Hardware:
    RPi1/Zero, RPi2, RPi3, +nodeMCU/ESP8266
    There are some possibilities depending on your software setup how "near" your led stripe is really is (distance between Hyperion and the stripe).

    1. Linux / MacOS (Windows)-> USB with a arduino. Hyperion could be installed on MacOS or Linux (inclusive grabber for the desktop). So this is the cheapest solution.
    Windows in brackets, cause Hyperion won´t run on Windows. If you could avoid Hyperion you could use other programs @Rick164

    1.1. Windows: There is a grabber available (works also with games) which sends the pictures over your network to Hyperion (Issue: you need a Hyperion running somewhere - like a Pi1/Zero behind you pc monitor)

    2. The other way how you could get the led data to a led stripe (longer distances or you want to avoid data cables) with Hyperion:
    Hyperion forwarder: Here you use an ESP8266 (also nodeMCU - which is easier to handle, cause you need to peform the voltage shift and a little bit fiddling flash procedure) and flash it like the arduino with a sketch. Hyperion will send the color data over WLAN to the ESP.

    3. How you connect a 4 wire (SPI) led stripe to a Pi could you see here:
    [​IMG]
    You don´t need to input the voltage at the beginning and at the end for a monitor (if it is not a 35"+ model)

    3. With (USB) Arduino: currently not much i could say here, there is a older tutorial which also points this a little bit inclusive sketch and troubleshooting. Never tried it out myself but i know many people use also a arduino.
    https://hyperion-project.org/threads/diy-amblight-project-guide-hyperion-ws2801-ws2812b-apa102.8/

    Power: You could use the same power supply for pi and stripe - so the ground and 5v is anyway connected from the same supply
    You could use 2 power supplies but then you need somewhere a connection to the GPIO ground pin. the Answer is, every power supply has another "ground value" (not sure how i could translate this better), the leds may not work fine if these different grounds are not connected to be "the same" ground.


    RGB headers mainboard: Looks like a usual 12V RGB led stripe control so no IC control for each led (SPI or PWM).

    Hope this helps a little bit.
     
  3. Doc.Ex

    Doc.Ex Member

    Messages:
    73
    Hardware:
    RPi2, +PhilipsHue
    The RPi controls the leds and runs hyperion, but you can let the pc grab the image digitally with the windows x11 grabber. It'll grab the image and send it via network to hyperion on the pi.

    Regarding the direction of the leds, it depends on the distance of your tv/monitor to the wall. If it's really close to the wall, definitely 90° angle. The larger the distance the more it has to face the wall. Ideal in most cases is a 45° angle.
     
  4. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    So I suppose I'll do the rpi3 behind monitor. And wireless to it from Windows. Swap it out later for something like a zero. Don't have one of those yet.

    For monitor it'll be about 6 inches or so from wall, slightly more at the curved edges.
     
  5. Doc.Ex

    Doc.Ex Member

    Messages:
    73
    Hardware:
    RPi2, +PhilipsHue
    6 inches is a pretty big distance. I would not recommend to have the stripes 90° to the wall. You would rather illuminate the whole room than just the wall. Those Leds do not have optics so they have a beam angle of about 120°. For 6 inches and 90° to the wall, this means that (in theory) you would have a darker ring of about 3,4 inches thickness around your tv. I would recommend a 30-45° angle. Sometimes you don't even need to cut and solder for those corners. I have seen videos where people were just looping the stripes or folding them for corners.
     
  6. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Okay so for the pi, why does the grnd have to go to the pi if it's connected to the strip?
     
  7. Doc.Ex

    Doc.Ex Member

    Messages:
    73
    Hardware:
    RPi2, +PhilipsHue
    The Pi and the LED strip need to have the same ground because it uses voltage levels as a data carrier. A TTL signal has 0V (low level) and 5V (high level) (or 3.3V). Voltage is defined as the difference between two potentials. So 0V is basically ground potential and 5V is a higher potential. When the Pi and the strip have a connected ground, they share their base potential so they interpret the high level the same way. But if you don't connect the ground, the strip could have a ground that is on a higher base potential than the ground of the Pi. So when the Pi sends a 5V signal to the strip, that potential could be only 2V in relation to the ground of the strip. That would result in a lose of data because the controller on the strip would consider it as low level. Hope that was somewhat understandable. Anyway, either connect the grounds directly, or use the same power supply for both the pi and the leds.
     
  8. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Well my plan was to use USB for Power so I guess I'll just do the ground, that makes sense though.
     
  9. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Bummer, just noticed my PSU isn't getting here for several days. Guess I can't set it up for a bit! I can get everything wired till then, or maybe use a 12V with regulator.
     
  10. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Just to clarify, I can do pins to the clock, data, power, and ground on the RPi and I would eliminate need for the USB power right?
     
  11. Brindosch

    Brindosch Administrator Administrator

    Messages:
    679
    Hardware:
    RPi1/Zero, RPi2, RPi3, +nodeMCU/ESP8266
    yes, you could deliver power over gpio.

    But:
    you lose the ampere fuse
    i still have issue with a stable voltage, looks like the AWG is not low enough if you use GPIO wires. bigger wires and soldering should fix this.
     
  12. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    So ideal then to just use a USB and terminate the extra power line(my strip came with a 4 wire connector and also a power barrel)

    In order to power the whole strip at full brightness I went with 5v 15A PSU
     
    Last edited: 17 June 2016
  13. penfold42

    penfold42 Moderator Developer

    Messages:
    741
    Hardware:
    RPi1/Zero, RPi2, RPi3, 32/64bit, +Arduino, +nodeMCU/ESP8266
    Just for clarity (apologies for the shouting .. It's important)

    DO NOT RUN YOUR LED POWER VIA THE PI IN ANY WAY.

    Don't rely on the Pi's USB input to get 5v on the gpio header.

    don't loop power via the gpio pins that are connected together.

    Don't try to power the pi via the gpio headers.

    There's lots of different reasons why each is bad, but in summary -

    DO NOT RUN YOUR LED POWER VIA THE PI IN ANY WAY.
     
  14. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Yeah I did some research and found that the 5v line is more for output than input and thus is not fused so if you don't have a consistent 5v or bad wiring you could easily destroy the pi.
     
  15. Brindosch

    Brindosch Administrator Administrator

    Messages:
    679
    Hardware:
    RPi1/Zero, RPi2, RPi3, +nodeMCU/ESP8266
    i attached 10V to the 5V GPIO by a fatal mistake, the overvoltage protection is still active you get some kind of short circuit over this fuse. Not funny but the Pi still runs after removing it ;)
    During this time around 2,5A where floating between this 2 GPIO pins (5v and GND). The board was very hot but no damage (at least it runs and behave like before).

    But yes, better not :)
     
  16. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Also I can just power the LED without connecting the Data/Clock right? To test my power.
     
  17. Doc.Ex

    Doc.Ex Member

    Messages:
    73
    Hardware:
    RPi2, +PhilipsHue
    Yes, however without a data signal it might just light up randomly or not at all. Not sure how that would be of any use to test a power supply other than basic functionality. It would be more useful to measure the output with a voltmeter.
     
  18. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    Sorry I have a 10A PSU currently but a 15A on the way, I just wanted to see if I could test brightness before wiring everything up to kinda have a base to go for.(that way I'm not overtinkering settings for brightness and such)
     
  19. Doc.Ex

    Doc.Ex Member

    Messages:
    73
    Hardware:
    RPi2, +PhilipsHue
    What do you mean by testing brightness? Do you want to measure the current your setup draws from the PSU on max. brightness? The thing is, when you connect the power, but no data and clock, the led controller chips have no input. So you can't tell them to go for full brightness. Usually the leds stay off or show random colours because of electromagnetic interference. A rule of thumb for RGB Leds is 60 mA per Led. So for 100 Leds, your PSU needs to provide 6A + some headroom. Maybe the Leds got more efficient by now, so usually you are save with that rule.
     
  20. Mysta

    Mysta New Member

    Messages:
    20
    Hardware:
    RPi2
    It's a 240 LED strip. I know I can't do full on 10A but wanted to get everything setup while I was waiting for the final PSU to come in.