Will USB-COM485-PLUS4 work with QLC+ and RPi ?

[chaosben]

At first i have to say: thank you very much for this great software. A week ago, we "rocked" a wedding with the support of QLC+.

For future projects i would like to build a dedicated box for controlling all the fixtures.
My idea ist to combine a RPi 2 with an USB-COM485-PLUS4 and controll it via WLAN and OSC.
The question is: will this config work and is it a reasonable config? Or should i use an more potential PC?

Thanks for thinking about my crude ideas.

[OddSocks]

Sounds like a plan that would work. My one reservation would be the USB-Com4 device, I don't know if QLC will talk to this device and send DMX commands out of it.

[mcallegari]

Uhm...not sure it will work.
How will you go from the DIN9 connector to DMX ?
How can a single device expose 4 outputs to QLC+ ? That's surely not integrated in the code.

[chaosben]

I would build a adapter from DIN9 to XLR (just connecting D+, D- and Ground).

There is no need for me, to use the 4-Port-Adapter. It was only the result of searching a cheap solution for more then one DMX-universe.
Do you know where to order cheap USB to RS485 FTDI-Boards in Europe or another solution lower then 40€?

[mcallegari]

Less than €40...hard to tell.

How many universes do you need to control ?

I am reading the COM485-PLUS4 datasheet right now and it says:

"Adds four RS-485 serial ports by connecting to a USB 2.0 Hi-Speed interface."

and again (talking about Windows drivers installation)

You will see four additional “USB Serial Port”, followed by a COMn assignment.
And four additional “USB Serial Converter A” ,“USB Serial Converter B” ,“USB Serial Converter C” and
“USB Serial Converter D”.

If I got it right and the FTDI micro exposes 4 serial ports, then maybe there's hope to work with it in QLC+ (maybe even out of the box)

No idea though if the Open DMX protocol will work flawlessy on all 4 outputs. Difficult to say without having the device.
How much does it cost ?

[chaosben]

How many universes do you need to control ?

At least i need 2 universes. But 4 would be great.

The USB-COM485-PLUS4 can be bought for 54€ which seems to be fair for getting 4 universes. Am i right?

@Robert: thanks for the hint. Could you explain "A resistor needs soldering across two of the pins" please?

[boxy]

I've used 3 of these in the past. I use a small plastic box and a USB cable to tidy things up. A resistor needs soldering across two of the pins:


http://uk.farnell.com/ftdi/usb-rs485-pc ... 0000005184

There's also this which I haven't tried but should work:

http://uk.farnell.com/ftdi/usb-rs485-we ... dp/1740357

[mcallegari]

Thanks Robert.
The difference with the adapters you shared and the PLUS4 is the number of USB ports used.
I imagine that 3 adapters on 3 USB ports are easier to handle than 1 adapter with 4 outputs on a single USB port.
The USB raw traffic must be devilish.

But now I'm curious about how it would work with QLC+

[mumbles]

what about using/ making the USB DMX controller I posted about making a couple weeks ago. I have one connected to a pi 2 right now. so I know it will work.
I have not tested pi with more than one though. So if you need more than 1 universe theoretically pi 2 should handle up to 4 of these FTDI usb dmx controllers without the need of a powered USB hub.

http://www.instructables.com/id/Pro-USB ... r-For-QLC/

[chaosben]

Thank you.

Maybe the last question: will RPi 2 be able to feed 4 universes?

[mcallegari]

Thank you.
Maybe the last question: will RPi 2 be able to feed 4 universes?

Short answer: in theory yes.

Long answer: I have tested 4 universes with 320 channels each (1280 channels total) via ArtNet. It works, but as far as I can tell the RPi is near to its limit when controlling them since the ArtNet plugin runs on a single thread.
In your case it would be different as every universe would run on a dedicated thread (which is better) but the RPi will have to handle the USB traffic.

I think you can only know when you try and, in case, report in this forum if it works or not.

[chaosben]

OK, thank you very much!