QM2000.Net & Wireless Network

[Jem]

Hi

I know this topic has been discussed before, but it never seemed to reach any conclusions.

I just wondered if anyone has managed to successfully link their computer to the QM2000.Net using a wireless connection instead of Cat5 network cable.

I'm not wanting something that is particularly commercially robust, 20 meters line of sight would be fine. If you've managed to do this what did you use to get it all working?

Cheers

Jem

[stanwax]

Jem
what sort of wireless kit do you have? Maybe if you have all the 'right' bits - laptop with wireless and a WAP to connect to the QM maybe we could have a go at the meet to get it working

Rob

[tocket]

This shouldn't be so hard. Now, I don't actually have QM2000.NET, but I really don't see any reason why it shouldn't work.

OK, so what you need is a WiFi to Ethernet link. They are usually called Access Points (AP) and are found in lots of places nowadays. You probably have one already in your gateway router. These are very cheap. If you're only connecting one QM2000.NET (can you control more than one at the same time?) you could just hook that straight up to a gateway router (on a LAN port). If the QM2000.NET supports DHCP it will configure itself just like your computer using the gateway router as server. When you connect your computer to the gateway (via WiFi or Ethernet) it will be like a direct Ethernet connection to the QM2000.NET.

That was the quick and ugly solution. It only works with one
projector unless they are close enough to each other to use network cable. A much neater solution is buying gateways that you can flash with a linux embedded distribution of your choice. This allows you to for example run the routers in wireless client mode; connecting to a central AP. It also gives many other options such as using them as wireless repeaters to extend your signal range and you can also install your own apps on them.

There are a few different distributions. Most are based on OpenWrt. If you are comfortable with linux you can use OpenWrt straight away, but if you are not I would recommend DD-WRT which is more user-friendly.

The hardware: Well, this software can be installed on many routers now. I have 2 Fon routers that I have installed DD-WRT (I currrently use this one as my internet gateway) and OpenWrt (just playing with this one so far... it's being difficult). Full lists of what routers they work on can be found on the respective sites. The Linksys WRT54G series is a safe bet though, as it pretty much all started with it.

If it isn't possible to run a QM2000.NET wirelessly with an OpenWrt-router, it isn't possible at all.

Links:
http://openwrt.org/
http://www.dd-wrt.com/

EDIT: Fon routers are really cheap btw. I got my last one for €10, brand new. You can also use them with bigger antennas as they have the standard RP-SMA connector for WiFi.

[Jem]

Well, i've got a wireless enabled laptop and a wireless access point with an ethernet socket on the back of it. What cable does this need, crossover or straight?

I remember now what one of the problems was... LivePRO does exactly what it says on the box i.e., it's controlling the lasers 'live'. Unlike say Showtime where the entire show is loaded onto the QM2000.Net card before the show starts to play, it is possible to unplug the computer and the show on the QM2000 will continue to play. This is distinctly different from LivePRO where there is a continuous stream of data flowing between the computer and the QM2000, I believe that when running LivePRO there is no data stored on the QM2000.

So, I believe the issues were with getting a fast enough data stream through the wireless network. I suspect this was a major problem with 802.11b/g, perhaps with the new protocols (N?) this isn't so much of an issue any more.

It's just one of those things that I fancied having a go at, to not have any wires between the projector and the computer would be cool.

Cheers

Jem

[Lampy]

Wireless would be very cool, but someone needs to make a bi-directional ADC/DAC type thing so we can sent the interlock signals and other projector-specific laser releated signals along side the ILDA standard signal.

-Matt.

[Jem]

Wireless would be very cool, but someone needs to make a bi-directional ADC/DAC type thing so we can sent the interlock signals and other projector-specific laser releated signals along side the ILDA standard signal.

-Matt.

Yes, I hear what you're saying about safety & I had already considered this. This is really just an experiment for my own satisfaction, certainly NOT for commercial use. Thanks for bringing the subject up though, any reminders about safety are always good

Cheers

Jem

[tocket]

You should use a straight, but lots of equipment today has autosense, so either could possibly work (depending on the router).

Looking at the QM2000.NET circuit it looks like it has onboard RAM, which suggests it can at least be used to store something, but the question is what? If you can load frames to it that could help even the network load. Even if that's not possible it shouldn't be a problem to run it over a 54g connection bandwidth-wise. Assuming you're sending 2 16-bit coordinates and 4 8-bit color coordinates 3 Mb/s would go as far as 47 kpps. I would expect a 54g connection to typically do 20 Mb/s, so there's plenty with headroom there... even with TCP overhead.

The only thing I can imagine being a problem is latency. Ethernet devices usually have around 100 µs latency, but for wireless it's higher, say 1 ms. Still, I think it should be fine.

Something really cool about using for example a Fon router with OpenWrt is that you can add a serial port to it and use that for the safety interlock (you could even add a web interface to it).

Take a look at:
http://www.dd-wrt.com/wiki/index.php...lling_AC-Loads

[Lampy]

Don't get me wrong, I'm not poo-pooing the idea! I really am interested in doing a similar thing over wireless or cat5. I'd really like to be able to have my remote panel with invert switches, e-stop, key switch, output power pot and status leds interfaced to the PC in some way so the signals could travel over wifi or ethernet rather than having the chunky multi-core I use now!

-Matt.

[p1t8ull]

There's a couple of threads in the "Networking" section of the Pangolin forum discussing wireless networks http://www.pangolin.com/ubb/postlist...t=0&Board=UBB5

[Jem]

...rather than having the chunky multi-core I use now!

That's one thing about the Pangolin QM2000.Net - It already uses Cat5 to communicate as it's network ready So, It should just be a simple case of sticking some wireless stuff in there and hey presto

If only it were that simple.

Jem