Is RPi the right option for me?

[richbass]

Hi All,

I'm putting a system together and having it run off RPi is very tempting, but I have some specific requirements and (having never used RPi before) I'm not sure if its the correct way for me to go. (The other option is a cheap notebook PC, but the RPi is much cheaper)

- I want a small self contained system, because I'm the bassist in my band and mostly have to carry my bass and lighting gear on public transport (trains, uber and London underground).
- I'll be connecting to two usb devices: an Enttec DMX USB pro, and a Roland UM-ONE mk2 USB MIDI Interface (which is a USB to midi cable that I use to connect my midi foot controller). I've already read that I'll want/need a powered USB hub.
- Ideally I want the RPi to auto start QLC+, load my file, and start playing. I'll be using the foot controller to trigger functions in a solo frame in the virtual controller. It'd be great to just power up the RPi, give it a minute or so to initialise, and then let it do its thing without having to use a screen or any input device other than the foot controller.

Is this realistic??

Please chip in with opinions and suggestions (that's something you don't hear much on the 'net!).

Thanks,
Rich

[mcallegari]

Quoting what is written in https://www.qlcplus.org/raspberry.html:

Boots in about 12 seconds on a RPi3 (15s on Pi2, 25s on Pi Zero and 30s on Pi1).
They start automatically in operate mode and with web access activated.
It is possible to define a project to be loaded and started at boot time.

Pretty much what you need huh ?

[richbass]

I read that, and yeah, it sounds perfect.
Sometimes theory and practice don’t aline though, so I was hoping to hear that no part of what I’m asking is gonna throw up issues.

What I’m still unclear on is whether starting a project means merely opening a project or does it mean running/playing a project(?)

Also, is the midi plugin fully functional on RPi?

Appreciate what you’ve created here btw. Awesome software.

[mcallegari]

QLC+ has a "design" and an "operate" mode. Opening a project alone will stay in design mode, which is not what you want live.
That's why the RPi image switches by default to operate mode, so your virtual console is ready to go, meaning it will accept signals from any configured input plugin.
And yes, MIDI is fully functional on the RPi too.

[Phil Smith]

Hi, Ive been using a pi and QLC pretty much how you are wanting to do for about 15 gigs now. No problems yet. I started off using a pi 2 headless (no screen) with a usb dmx dongle and a midi controller LPD8 straight into the pi. It auto loads my QLC project and outputs dmx straight away when I turn on the pi.
I then discovered this http://www.qlcplus.org/forum/viewtopic.php?f=7&t=11616 and have since got rid of the USB dongle so now I have 4 parallel XLR outputs on one universe and a more robust case, I was worried about the flimsy micro usb power connection getting accidentally trodden on on stage. This new box is much more durable. This also means I have the old system as a backup if my new one goes down, small and easy to carry and only cost £40 as a backup.

[richbass]

Thank you both for your replies. Brilliant. This is going to be so much a better system than having to lug a laptop around. I’m really looking forward to getting this sorted out.

One last question...

A couple of the sites that sell RPi kits come with a preloaded SD card (different flavours of OS I’m guessing). Is there a ‘best’ starter kit / OS I should be looking at getting? A recommend retailer in the U.K.? (I’ll be going for the lastest 3B hardware, unless you suggest otherwise).

Thanks

[richbass]

Phil,

I’ve just been checking out this post you shared. Looks fantastic. I’ll get the RPi running with my enttec dongle first, but once that’s all running this will definitely be the next step. Thanks

I then discovered this http://www.qlcplus.org/forum/viewtopic.php?f=7&t=11616

[mcallegari]

One last question...
A couple of the sites that sell RPi kits come with a preloaded SD card (different flavours of OS I’m guessing). Is there a ‘best’ starter kit / OS I should be looking at getting? A recommend retailer in the U.K.? (I’ll be going for the lastest 3B hardware, unless you suggest otherwise).

The official QLC+ RPi software is a complete image that you will write on a SD card. So you don't need a preloaded OS at all. Just purchase a Raspberry Pi alone and an empty SD card from wherever you prefer. Class 10 SD is preferred if you want to get the boot times indicated in the QLC+ Raspberry Pi page.

[Phil Smith]

I use pi hut:
https://thepihut.com/products/raspberry ... del-b-plus
I have used the cards with NOOBS preinstalled but as Massimo says his image supplies everything you need. He'll send you a download link after you've made a donation.

I tried building my own image which I found educational as I'd never done it before, it was long winded though and I didn't get UART output (worked fine with my usb donlgle output) which is something I needed for my 4 way XLR project.

Using Massimo's image also had its own challenges as I think its a very bare bones image so I had to learn a few command line functions. Unless I missed something and you can get to a normal desktop UI somehow.

[richbass]

The official QLC+ RPi software is a complete image that you will write on a SD card. So you don't need a preloaded OS at all. Just purchase a Raspberry Pi alone and an empty SD card from wherever you prefer. Class 10 SD is preferred if you want to get the boot times indicated in the QLC+ Raspberry Pi page.

Perfect! I’ll definitely be making the donation for your image when the time comes. Again, thank you!

[richbass]

Thanks Phil

Being able to pick the brains of a user and the developer is priceless.

I’ve done some coding in a previous life, so I should be ok with command line stuff, but I know where to come if I have any issues

I’ll be ordering the remaining fixtures this week (hopefully), then the stands, then I’ll be able to get the RPi and image. Very excited!!

[richbass]

Using Massimo's image also had its own challenges as I think its a very bare bones image so I had to learn a few command line functions.

Hi Phil,
so I got my pi, and installed Massimo’s image; all simple there. Took a while to learn how to configure the ethernet port for web access; now done. Even managed to copy a fixture profile via scp over ssh!

I’m having an operational issue now with midi, in that my functions/widgets don’t trigger properly; they sometimes flash when the controller button is pressed, sometimes not, but don’t properly trigger the widget. Did you have any issues with an external controller?

[Phil Smith]

Hi,

I do have some problems that I confess I haven't spent enough time to iron out and have just accepted for now. When I wish to trigger widgets/buttons I need to click buttons on my LPD8 twice when I would prefer to just do it with one click. I am sure I could work this out on my own but haven't had chance to spend the time figuring it out. I imagine I'm just using QLC+ incorrectly. Afraid I'm on holiday at the moment so cant fire it up to look at any settings.

I haven't had the problems you describe with web access, when I plug the pi via Ethernet into my home network it just works without any of the hoops you had to jump through.

[richbass]

I've had thoughts of things to try when I get chance to try and figure out exactly where the problem is, but even trying to trigger twice doesn't solve my issue.

I'm sure I read in the main user manual something about double triggering for some external devices. It might be worth having another read through the main manual again, as it may solve that issue.

This is certainly being a learning curve, but I'm sure I'll get there in the end.

Hope you're having a great holiday.