Small Form Factor RaspBerry Pi Projects

Hey guys,

I've just finished unpacking a bunch of stuff from moving house and I discovered my old Pi Model B which I thought I had lost. I also recently purchased a Pi 2 B which I had been playing with and set up as a Minecraft/Terraria server (but they never ran that well).

Having set up a Beaglebone Black as a datalogger for our Solar Car (while we use our own system, it's all CAN-bus so the premise is the same; if anyone wants a guide on how to do this I have a few bits of documentation I put up on Github which I could cobble together into a mini-guide) I'm tempted to put my Pi's to good use.

What have other peeps been using theirs for?

 

KODI Box

Sent from my Nexus 4 using Tapatalk

 

My old man built his into the van as a sat nav

 

Project: BBC iPlayer server for the Raspberry Pi

http://thedigitallifestyle.com/w/in...ject-bbc-iplayer-server-for-the-raspberry-pi/

There is something to try maybe.

 

I've just noticed that Plex now has a Pi2 distro, so I might give that a go and see if I can ditch the HTPC entirely.

 

Kodi + Plexbmc + Moonlight

Kodi does all your standard media center stuff, plexbmc is fully integrated in the the GUI if you use the right skin (Amber works well), and Moonlight basically turns your Pi in to a Steam Link as long as you've got an Nvidia card in your main PC

 

Currently building a solar panel utiliser

Basically calculate how much extra power the solar panel is generating, and turn on appropriate power consumption devices, to minimise solar panel exporting automatically => maximum profit.

 

Done the kodi / openelectric thing. Thinking about setting up a puppy cam to watch the dog when we are out.

 

Well I've ended up trying to make a semi-headless media centre / audio player controlled by only 2x20char lcd + pushbuttons to act as a lightweight carpc.

I think I have most of the sotware side worked out, just needs some legwork to do all the programming/configuration I want.

Next big step is to try and fit everything into a standard din unit and make a nice front panel.

 

Why isn't this a build log?!

 

Well at the moment there's a lot of fiddling with getting stuff to work and not much actual build/design atm.

In other news my VFD display arrived today. Unfortunately it didn't work with the HD44780 protocol like I was hoping (should really have checked the datasheet more closely) so it wasn't a drop-in replacement for the LCD I was using. Fortunately lcdproc already had a FutabaVFD driver available (although I had to recompile lcdproc to get it):



The (vastly overexposed) photo doesn't do it justice, it's beutifully clear in the flesh.

One blessing is that I'm now driving it in serial mode rather than parallel which leaves a lot more GPIO free for buttons. My current play is two rotary encoders (one for menu navigation and one for volume) plus a full set of audio controls (play/pause, rw, fw, stop) but I could easily fit more on, provided I can find the space.

EDIT: Does anyone know the best way to do nice switches for a brushed aluminium panel is?

 

What sort of switches? Could turn some on the lathe.

 

I was thinking bars, but actually round switches work as well.

The main issue is more the mounting them and the switch mechanism. I could probably do a pcb with pushbutton switches on it (or even membranes, although don't know quite how to do that) but I don't know how well that would hold them in place.

I kinda want a cd-player as well, but unless I can find a very sllimline one I'm going to struggle to fit everything in a single DIN slot.

 

Push buttons would just be round, with a bevel to keep them in place in the hole and their back resting against the face of the PCB microswitch, for instance. Big rotary knobs would just fit over the axle of the rotary switch.

 

Yeah, that's what was thinking, although with long rectangular buttons as well. A bit harder to machine than circular buttons albeit. Out of interest, how easy is it to annodize aluminium black?

The other option is some black backing material behind a plate of semi-transparent acrylic for an ultra-clean look. I could even go with capsense switches.

Time to start learning some Kicad methinks!

 

Naah, rectangular buttons are easy with a mill.

 

Mini update, will probably kick off a mini project-log at some point:

I have been fiddling around with skinning in Kodi trying to get the interface working with only three buttons. It's a big task to begin with, but unfortunately there are certain elements (e.g. your music library) which Kodi fills in automatically. This means that I'd have to pretty much recompile Kodi to get what I want working (it can probably be done with addons, mind).

Fortunately, while I was asking about it in their forums someone mentioned adding a "longpress" option to the enter key in my keymap. Now this doesn't actually work since Kodi doesn't actually handle the 'longpress' modifier from regular keypresses. However, since I already had a script to handle button inputs and send them as kepresses, instead I just changed that to sned a backspace if the switch was held down for more than a second. I then realised I could also make the encoder act differently when the switch was pressed down so I added that in as well. The code is a little bit messay at this point, but to be honest I'm not going to lose much sleep over it since it would be pretty hard to do nicely.

So I've now mapped to following:
Short button press - Enter
Lont (>1s) button press - Backspace
Encoder clockwise - Down
Encoder anticlockwise - Up
Button pressed + encoder clockwise - Left
Button pressed + encoder anticlockwiseclockwise - Right

This should be enough to handle all the inputs I need to control pretty much any skin in Kodi (I'm considering adding a V.long button press to send a 'Home' command, but we'll see how that goes). All that I have to do now is tidy up the interface a bit so it seems a bit more intuative with just the 2x20char display.

In other news I've been mocking up what the front panel might look like. I've been working off dimensions of 180x50mm to fit a standard single-DIN compartment. I had the idea of setting the VFD display back a little bit to make a bit more room so the pcb for the buttons can sit in front of the PCB of the VFD instead of having to go beneath it. While cleaning out the back of my car I found my 3mm smoked acrylic (which i had bought for doing the dash of our Solar Car a while back) which was perfect for the job. I was slightly worried that offsetting the vfd would mean some of it would be hidden since the HU in my MR2 is pretty low down, but it looks like I will just about get away with it based off of the CAD.

Here's the mock-up in question:



I'm also planning on having 2 little round buttons on each side under the encoders. The only real issue with this is fitting all the traces on to the little bar board, but that shouldn't really be a problem. It's also one more thing to mount, but oh well. I'd also like to get some symbols engraved, but I have no idea what the options are for doing something like that.

Other than that I'm still wondering about mounting the PCBs. I think having one big PCB is out of the question since it will be oddlyu shaped (and therefore big) and I'm not sure the 1.6mm FRP would be rigid enough to stop it flexing. I think the best idea might be a metal backplate, which has the added advantage that I can adjust the clearce for the buttons with spacers if needed.

Ultimately I want to gather all the connections together onto one board with a ribbon cable to the pi (and possibly have all the pi's header's broken out on the board for future expansion) but we'll see how that goes.

 

Audio project:

• Raspberry Pi + DAC HAT + headless Spotify client (self developped)
• Dual mono amplifier (DIY)
• TQWT using fullrange Supravox drivers (DIY)

Gaming project:

I recently bought an Odroid-W, which uses the same SOC than the Raspberry Pi A+/B+. The differences are:

• 2x 12 bits ADC connectors
• RTC clock
• LiPo battery header
• Battery "fuel" gauge
• eMMC connector
• half the size of the Raspberry

Planning to use it to build a retrogaming handheld console.

 

Just got my Coupe case and heatsink for the Pi3. Would be rude not to try overclocking now!

 

What do you use the Plexbmc for...I mean what does it do that Kodi doesn't?