Raspberry Pi+JMRI+PR3XTRA+wifi adapter=portable Wifi Throttles? Now on a Netbook

[rsn48]

I bouncing this thread to a friend who is into Raspberry Pi, JMRI 3, Decoder Pro, etc to see what he has to say.

[rsn48]

Hi Rick,

You can forward if you like.

I'll repeat some of what you already know for others sake.

I'm not a Linux guru, I'm just getting started with my Raspberry PI B+ but here's my progress report and goals.

I want a portable JMRI set-up mostly for Decoder Pro3, anything beyond that is gravy.

The latest update check for Java on my XP machine cautioned me that while the latest version may work, it's not a certainty as XP is no longer supported.

A new computer is not in the cards, so Linux it is...

Finally caved in and bought the B+.

Plugged in PR3, wireless IOgear-mini-keyboard-and-trackball-dongle, net cable (no wifi yet) and my HDMI TV to get it up for testing.

Installed NOOBS Raspbian as per www.raspberrypi.org

Java is part of the image, so you don't need to install it!

Selected boot to GUI, (this will let you snoop around, but takes more resources, so my next move is to boot to command line and see if JMRI will start).

Downloaded the latest Linux JMRI and unzipped to a folder on the Pi desktop.

Opened the folder and double clicked on Decoder Pro3.

Prompt asks what you want to do, select execute.

No install, it just runs. Be patient, give it a chance to react.

Go through the preferences under "edit" such as PR3 etc.

Save and JMRI will prompt to restart.

Got through the menus and started the servers, web, withrottle etc.

I'm using a router to handle the network load and free up Pi resources.

My Android tablet (Engine Driver) found the server and let me select from the roster I'd imported from my XP machine via a thumb-drive (also how I copied the unzipped JMRI folder). No track at this point but no problems.

Picked up a used monitor that I'm going to zap-tie/Velcro the Pi and PR3 to.

Connected to a yard of flextrack and changed the address of a loco.

Next I grabbed my Bowser Baldwin with Loksound and read all 1200 CV's in direct mode, it chewed on it for about half an hour but that's about normal for the task on any system.

Next will be finding a wifi dongle that will work as an access point (mine won't) for portable use away from home. I've read they're limited to 5 connections.

I may overclock for improved speed, try faceless mode etc.

I hope this answers some concerns, if you don't like it, use the Pi to convert your milling machine to CNC or build a 3D printer etc.

It's not fast, think Pentium II, but there are no moving parts, the hard drive is a (micro)SD card.


It wasn't a waste of $50 for me.

I forgot to mention a frustrating/confusing part of the R-Pi install, is that the configuration menu is navigated with the [TAB] and [SPACE] keys as well as the arrow keys, not the [ENTER].

Scroll to the desired item with the arrows, hit [TAB] to highlight "select" or "finish" and hit [SPACE] to execute.

Another catch, at least with my keyboard, in some cases (login prompt for example) the [ENTER] key doesn't work, [CTRL]+[M] does (a throwback to TTY terminals).

Many older programs are like this, newer ones often use M$ windose conventions, [CTRL]+[C] for example if memory serves, was an escape command not copy, [CTRL]+[Z] was end-of-file not undo.


Cheerios,

D. R. MacDougall
(Eccentric Crank)

[Iain]

I reckon I can weigh in here, since I know a thing or two about Linux and ARM.

First, I would go with a Beaglebone Black.  Sure, it's $10 more, but, you get a more modern ARMv7hl processor that has proper kernel support as opposed to the ARMv6l SoC in the Raspberry Pi that does not have full upstream kernel support.

I have a PR3 Xtra I had been planning on playing with until I started packing to move.  I had a similar idea.  My thoughts were as follows:

I've rebuilt RHEL 7 for 32 bit ARM; toss in a few extra things not included in RHEL that are needed for 32 bit ARM (like u-boot) and possibly the 3.17 or 3.18 kernel to get a bootable  image for BBB (Beaglebone Black).

Plug a USB wireless dongle into the USB port and just set up networking/dhcp so that it will work as an access point.

Write a systemd unit file to auto start all the jmri bits needed, so the system could be totally headless.  For access at shows if needed, I have an ssh client on my phone.

If you're interested in what I come up with, I can put the filesystem image online somewhere for download.  I do not know how you would go about writing it to an SD card in Windows, but in Linux just dd bs=4M if=<image file> of=<sd card (usually /dev/mmcblk0)>

If I were to do this, you should be able to just write the image to the SD card, plug everything up, and it just work.

If you're interested, let me know, and I'll poke at it once I get moved.  Just note that anything I do will not work on the Raspberry Pi due to its out of date SoC.  It's the equivalent of running software built for newer Intel CPUs on really old Intel CPUs; the instruction set changes over time.

[rsn48]

I would be interested.

[delamaize]

I've been doing a lot of research, and the more I think about it, the more I think that a Netbook instead of a Raspberry pi or a Beaglebone will meet my needs, and allow the "wifi module" to preform more functions, like an on the spot programming track, or the ability to monitor who is connected. At this point I am doing testing with my home Laptop, and researching right now, so far I am happy with the results. Once I find a cheap Netbook, I'll probably pick one up, and transfer the testing to it. Once I feel comfortable with the setup, I'll start designing and fabricating the box for the whole thing.

[delamaize]

ok, so testing resumes...
Today I was able to find a older Belkin G router at a local 2nd hand store, with no power adapter. Luckily, I had another Belkin router that is shot, and had a similar plug and power requirement. The "new" router requires 5v and 1.5a, the power adapter for my "old" router is 4.5v and 1.5a, close enough for me, and apparently for the "new" router also. So, I got all the hardware components, and I am continuing testing. Now the set up has it's own network, and it's all working well. It has been tested with both Android and Apple products now, ad functions well with both. My android phone is pretty damn handy, and works flawlessly. the Apple product (iPad) is pretty nice, although a little large to lug around at the train show. Overall, hardware wise, smaller devices are easier to handle, but the tablet sized screen is nicer for use.

I think the whole setup is pretty damn close to being ready for larger testing.

So, Overview, I am using a little HP Netbook, the PR3 xtra, and a belkin G router, and my Samsung Galaxy S5. The Netbook is using the the newest version of JMRI, on Android is Engine Driver, and on the iPad is using WiThrottle.

The plan now is to do a little more testing, I am trying to make it fail somehow, and so far, I don't think it will. Next, I am designing a box the whole thing will fit into, with the target being something almost as portable as a DT200 or something like that. Ideally, I would like to be able to be able to plug into a Loconet site, and plug into 110v, boot the computer, and in about 1-2 min be up and running. The software is at this point already.

This is getting fun, Stay tuned!

[x600]

Me and my android are watching closely.

Greg O.

[delamaize]

Me and my android are watching closely.

Greg O.

Depending on how the rest of the week goes, I may bring the set up, sans box, with me on monday/tuesday......

[Mark W]

Saw this today on how to take back 48mb or RAM from the GPU.  Might be useful for this project.

http://imgur.com/a/p87pB

[delamaize]

The JMRI-Wifi-innabox hardware stress testing has been going well. and thus far I have ran into only one issue, that I can't seem to figure out. for some reason, only with my phone, it will think it has lost connection to the JMRI server, and stop communicating with the server. Although according to the software on the computer, it's still connected. The problem seems to have resolved it's self once I moved to a dedicated router. I also have discovered that small screen tablets work the best with Engine Driver. The larger size of the screen makes the controls a little easier to use, and the text is a little easier to read. Although, I wish it when it rotated to landscape it would move the throttles side by side rather that vertical. THAT would be awesome. Although it may do this, and I have not figured out how to make it happen.

I'm hoping that I will be able to do some larger scale testing in the near future, once that is accomplished, I will pick up the pace on designing the case for the whole thing.

[Iain]

Sounds like you might have been having packet collisions, no idea how to diagnose that with Windows.

[Sokramiketes]

I've set this up on the Modutrak layout a couple of times and the random dropping of connection is an annoyance.  Seems to be triggered by anything from receiving a text message to having a notification pop up.  Sometimes you get in a loop where you can't acquire a loco either. 

While the set up sounds complicated, all you really need is a router to provide a wireless network at the layout, a laptop running JMRI, and a Digitrax PR3.  I'm not sure where the raspberry pi comes into play, or Linux.

[C855B]

... I'm not sure where the raspberry pi comes into play, or Linux.

As a compact "black box" replacement for the laptop.

[reinhardtjh]

For anyone still interested in the black box appliance type install. Micro Center  once again has the Beaglebone Black on sale for $39.99 - $15 off the normal price.  http://www.microcenter.com/product/434844/Element_14_Beaglebone_Black_-_Revision_C

[Mark W]

Raspberry Pi 2 announced.  http://www.theregister.co.uk/2015/02/02/raspberry_pi_model_2/

Same price as the B+, but now with 900MHz processor an 1GB RAM vs 700MHz 512MB RAM on the B+.