I am new here, but I am curious of this library.
Does anyone knows the DM164 ic? The G-Lec led matrix use this ic to control the LEDs, and I saw on concerts and I think is’s works wotihout flickeringa and even on large size of panels. I am looking for something similar for my next project but can’t decide witch LED (and controller) should I use to get non or very low flickering, low latency and fast controlling, ability of programing in the future, so less restriction. And please refer controller as well. In the future I have to control everything from a server thru the internet, which OS are you recommend to get the best stability controlling system?
I haven’t seen it before now. Some numbers interpolated from the datasheet. It’s 16-bit pwm (instead of the 8-bit pwm that most of the chipset supported by FastLED run on). This means that there’s twice as much data to send (48-bits per rgb pixel vs. 24-bits), and with a 30Mhz max data clock rate that’s about 625,000 rgb led updates/second (or ~10k leds at 60fps).
However, it has a pretty slow pwm rate, only about 450 hz (the PWM clock runs at 30Mhz as well, but because there’s 65536 levels of pwm vs. 256, you only have the 450Hz pwm refresh rate). This is on par with the WS2812’s but with APA102’s giving you ~20khz refresh rates, that’s a little disappointing (but again, understandable with the 16-bit PWM levels).
As far as advising you on what to use, knowing more about what you’re thinking (size of project, number of leds, etc… whether you plan on doing all your pattern generation right on the controller, or if you intend to use the controller as a dumb frame buffer for effects/visuals generated on a computer (note that this is different from remote control), etc…) would help with actually giving you advice.
i worked with the Gelc system many times , it was one off the first transparent led screens. German made , but with a lott off limitations and struggle to keep it to work .As Daniel specified this is a low frequentie screen 450 Hz , only has a dvi input at 640 x 480 .
If you want to build a solid screen 16 bit driver look to the chinees control systems . Adadfruit is promoting the most common Chinees Linsn system . This is one off the 10 different chinees led controller there is on the market for those screens
Colorlight , Novastar , Dstar and Yelo are other systems with a more open architecture witch you will need to build your screen . All those system can drive a 8 bit or 16bit led drivers . They all are dvi input and linked by a network protocol with dedicated control software … Price is from 350 for a input card to average 50 dollar for a output card . All chinees led screen are build around those “blocks” …
But if you want to build dedicated predefined led effects on a screen , do it with Fastled and arduino style board … it is a challenge but also great fun .
Thanks for replying.
I understood that the dm164 won’t fit with my plan, which is Ok, I just mentioned, because I saw the picture was good, and non flickering and I would get something similar result with something else.
So if you just recommend a type of LED with driver chip, controller, and realible computing system what you think will able to fit more with this requirements:
-Approx 2000+ rgb LEDs (but max 5000)
-Different shape of screen, even circle or triangle, and attached shapes from these
Control the screen with a client local device wich runs the code and get update from the internet (I would use pc, but thinking on the OS)
-Make it interactive with: camera, touch sensor, mic, light sensor, and play video from analog video input
Art picture Visulation like smartmatrix, or fadecandy led art, like equaliser and play video.
There’s a lot of options, there really isn’t any one recommended option, it would come down to what you’re comfortable with doing, what hardware you have available, where your skill level is, etc… etc…
I would probably do up to 2000 off of a single teensy 3.1, with all the pattern generation happening on the teensy 3.1 with an outboard bluetooth board allowing for parameter control from an iphone or some other device.
From the variety of things that you want to do with it, and given that you want external, and likely, PC based control - what I’m tempted to recommend to you is that you look into using FadeCandy boards to drive WS2812 leds (512 leds per fade candy board), and drive those off of something like a beaglebone black or a raspberry pi, or worst case scenario, you could drive them off of a PC.
Generally speaking, whenever someone starts asking for PC/computer based control, I direct them at FadeCandy, mostly because FastLED is really geared towards running everything on a single MCU for completely self contained pieces. (You can wedge things with FastLED to have the bulk of the image/led data coming from computer, but it’s a pain to do and do well, and I find it irritating to support, and FadeCandy has already solved that problem)
Thanks Daniel for your explanation.
I understand what you said, there is many way to succeed my project. What is my priority is: the stability, I heard that the APA102 is (one of) the most reliable LED because of the separated CLK and DI lines and the refresh rate, as I know the WS2812 has just 400hz.
So this project would be for daily 18-24 hours use, so I would use these APA102 leds (or something similar), if you are agree with my argument. (I am not sure, and you have got experiences).
The Fadecandy is a good chance, but as I found I can’t connect the APA102.
I realised that the Teensy can drive those LEDs but can’t control by PC, is that right? What solution could you suggest?
And also, how can I get the less latency as possible for the eq visualisation?