rich_steed
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Pi board ideas please

Tue Jun 06, 2017 2:11 pm

Hi guys,

I have a set of Raspberry pi model Bs in my cupboard at school. We currently only have VGA monitors in the classrooms and no spare plugs or network ports to use.

So I had an idea...... I am planning to mount the pis on a board, set them up to SSh using static IP addresses on the school network. I will fit each with a different device like pi glow, LEDs,cameras, temperature sensors, etc. The idea would be to get students to write code in python on the PCs and then run it on the pis using SSH to connect or just connect directly and write code on the pis

Do you think this would work and can anyone anticipate problems?

ghp
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Re: Pi board ideas please

Mon Jun 12, 2017 5:39 pm

Hello,
think this would work. The only constraint is that ssh is disabled by default for new raspbian distributions.So be prepared to boot each SD card with keyboard and monitor at least once to enable ssh.
If you register the mac adresses in the network infrastructure dhcp server with fixed ip address, you do not need to reconfigure fixed ip address each time on the pi when you reflash cards.
And if you provide an extra LED for each of the pi with a small blink program, then each user can easily check on which computer being logged in.
Hope this helps,
Gerhard

ElEscalador
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Re: Pi board ideas please

Mon Jun 12, 2017 7:38 pm

It *could* work but I think SSH only access might be difficult for kids starting out. Why not have them use VNC to use the PI's just as if they were plugged in - with a full GUI console and everything. Then they can write code with an IDE right on the PI...which I think is easier to learn than learning with the nano text editor and command line compiling.
A few of my projects below.

https://www.youtube.com/playlist?list=PLdlhFMXxFUNlMpeqHipdSIO20pb4piHfj

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winkleink
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Re: Pi board ideas please

Mon Jun 19, 2017 4:31 pm

Love this idea as it allows physical computing within the confines of the school set up.

Have a look at PiBakery http://www.pibakery.org/
You can pre-configure your set up with VNC and/or SSH enabled.
You can also set a different host name for each Pi so you know which ones the kids are logged into.

ssh can be enabled by adding a blank file called ssh to the /boot folder.
This is the partition Windows can read when you insert the SD card into a Windows PC.

Another possible setup could be.
Enable SSH
Use Notepad++ on the PCs with the ftp plugin
http://www.averagemanvsraspberrypi.com/ ... lugin.html

In this way the development is done using the power of the PC. The code is transferred to the Pi from Notepad++
The need for ssh is purely to run the code.
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OutsourcedGuru
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Re: Pi board ideas please

Mon Jun 19, 2017 11:58 pm

If each of the Raspis are loaded with the full/PIXEL version with the desktop interface, then you can turn on the VNC Server in raspi-config, reboot, configure it in the upper status bar of the desktop interface and then it's running.

You then may VNC into the desktop side of things on the Raspi and it's probably a more welcoming interface for kids than the terminal/SSH. And you can still drop to the Terminal from within the desktop interface.

If your workstations are OS X then in Finder, Cmd-K, vnc://pi@hostname.local (password raspberry) and you're in. Personally, I'd suggest naming them each with the names of minions: Dave, Stuart, Bob, etc. If you add a speaker to each Pi, then you can `aplay` a local sound file on the Pi's speaker, say, in the ~/.bashrc login script. So, Dave would play a sound event with Dave's voice when someone remotes into Dave, etc.

The desktop has some cool programming options from the menu. Node-RED might be an easy starting point.

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PiBakery
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Re: Pi board ideas please

Fri Aug 04, 2017 2:58 pm

This is exactly what I did at my school, as we didn't have any monitors at all. It worked really well, provided you were able to identify the IP address of each Pi without powering it on.

As ghp has said, the best solution for this is to register the MAC addresses of the Pis in the router, and that way you can reflash SD cards and also take them all out, upgrade them, and put them back in again and don't have to worry about matching up the cards to individual Pis.

There was, however, one difference in your setup compared to the one I did, that you may want to consider. Having a class of 20 Pis all connected over WiFi to the same router is fine, but when they all run VNC at the same time things may not be so fine. It really depends on the type router, the network, the location of the router compared to the classroom, etc.

Obviously, SSH would solve this immediately, but is a lot harder for a class to use. I wouldn't recommend going down this method.

However, one of the most underappreciated programs for the Pi (in my opinion) is Adafruit's WebIDE. It's a web interface that allows you to write Python (or other languages) code easily, and run them on the Pi. I've used it with a class before, and got excellent results. By default all the code is stored on BitBucket, but this can be easily changed so it's stored either on GitHub, or on the Pi. See the Advanced Options section for more info on this.

Only last thing to add is that as the Pis are headless, the likelihood that they'll be shutdown properly is decreased compared to having a monitor (people forget to shut them down using the WebIDE, and then the plug is pulled on them while they're still on). This can cause the SD cards to become corrupted, and while this is very very rare these days (and well done to the Pi Team for reducing this significantly), it's very very very useful to have a few extra SD cards with the software flashed on them that you can just swap in and use instead.

Good luck, and if you need any help or want more details from someone who's done what you're trying to do, I'll be happy to help.
PiBakery - The easiest way to setup a Raspberry Pi
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