Jump to content
Do Not Sell My Personal Information

Project D-d

Recommended Posts

Project D-D. AKA Project Dash Droid... Perhaps this gives a bit more of a clue as to what I am working on

So, what’s the big fuss of the secret?

Well... who doesn’t like a bit of mystery?

As most of you may know (or soon will!) - I am a tightwad, I have fancied something nice and shiney for a while, but I don’t fancy paying the ludicrous fees for it! £300+ for something I already have quite a few parts for? Where is the fun in that? you have customised your car - sure, but where’s the love?

Anyway, I fancied a new head unit, something androidy, something with plenty of customisation and plenty of entertainment! Enhancing the car further than it was initially designed to go, and by heck I plan on doing that! So, I took a Nexus 7 I had laid around, gathered a few cables and started doing some research.

(This part is educational, feel free to skip to "what do I want from my tablet if you don’t care :) )

Those of you who have a nexus 7 know it’s awesome, but it has a big limitation - it can’t charge and use USB at the same time! so I had to look into this and find a custom rom which would allow it! a bit of research later, and I am pointed to TIMUR's distribution of Android - "USB ROM" based on CyanogenMod 10.1. This would allow me to charge the tablet and use USB at the same time! first hurdle complete!

So ... What did I want from my tablet?

well... not much... just the following...

⦁ DAB Radio (without using internet!)

⦁ SatNav

⦁ Phone (and text message) integration

music Player - with extendable USB Connectivity.

⦁ Car diagnostics and dashboards (of course!)

⦁ Parking Camera function

⦁ Internet Browsing (for when I am stuck in OPERATION STACK [which, seriously is annoying, as I started to write this, it was in effect, has been for about 7 out of 10 days and in fact 4 times in three months, and seriously makes my journey a misery)

⦁ Freeview TV - a nice to have, not essential - but I won’t give up on it! Technically its illegal to use while driving anyway, so less priority than the rest

⦁ Traffic announcements - preferable, but I could probably live without! (Found an app that might do the job if the radio doesnt!)

⦁ No damage to the car wherever possible!

So as you can see - I didn’t really want much from it! So, I start doing some research, and I love it when a

plan comes together!!!

Let’s go shopping!

So, some of this is necessary, some isnt, but I will put it in so you get a wild idea of the most expensive part.

This is a conclusive list of all costs, after I had played with bits here and there, I have corrected prices below accordingly: 

⦁Nexus 7 tablet - £120 or as little as £40 used with a “fault” on the screen – which isn’t a fault…

⦁OTG Cable - £5 - £8.26

⦁Power Cable - £3

⦁Freeview dongle and aerial - £10

⦁USB Capture Card - £10 - Not Used

⦁USB Hub - £6 - Not required, as the OTG cable has this

⦁Fascia - £15 - 

⦁Beefier Aerial - £10 - Not Used

⦁Aerial Extension lead - £1 - Not Used

⦁Software - £15 - £55 (software referenced below)

⦁Replacement Stereo - £20 or so 

⦁Stereo Wiring - £20 or so

⦁4x 5v 5a USB output - £3

⦁IR Repeater - £8

⦁Aerial Splitter - £20 or so

⦁Joyconn EXR Steering Wheels Adapter - £20

⦁Time and Patience - £Priceless!

So, that’s the main bulk of the hardware bought - or not! so far, I had most of it, I needed a few small bits -



OK so here is all the software I used (With links) in case anyone is crazy enough to copy me...

⦁Nexus 7 Rootkit - this allows you to root your tablet and start flashing software onto it. http://www.wugfresh.com/nrt/

⦁USBROM - your new android operating system. http://mehrvarz.github.io/nexus-7-usbrom/

⦁Co-Pilot - SatNav - https://play.google.com/store/apps/details?id=com.alk.copilot.mapviewer&hl=en_GB

⦁CarHomeUltra - Complete Interactive Layer for the car - https://play.google.com/store/apps/details?id=spinninghead.carhome&hl=en_GB

⦁Poweramp - music Player https://play.google.com/store/apps/details?id=com.maxmpz.audioplayer&hl=en_GB

⦁Music Volume EQ - Allows a simple touch screen volume slider. https://play.google.com/store/apps/details?id=hr.podlanica&hl=en_GB

⦁Tablet Talk - Allows you to set phone calls off from your tablet / send SMS - then uses your phone for the dirty work! https://play.google.com/store/apps/details?id=com.apdroid.tabtalk&hl=en_GB

⦁AutomateIt - Allows automation of the tablet -  https://play.google.com/store/apps/details?id=AutomateIt.mainPackage&hl=en_GB

⦁Torque - (of course) for car interaction (free or pro -both work) - https://play.google.com/store/apps/details?id=org.prowl.torque&hl=en_GB

⦁Gel Icons - Just to make it look a little better!

⦁Wavesink - Allows you to listen to DAB radio without internets

  • Like 4
Link to comment
Share on other sites

Software Building Time!

Lets start with the software, first thing that was needed was to take my stock Nexus 7 - I needed to install USB ROM so it could charge and use OTG devices at the same time. Standard Android doesn't have this by default, if you do not use a nexus 7, you will need to ensure any custom ROM you use, features the simultaneous charging and OTG access functionality enabled.

Using Nexus Root Toolkit (NRT), you will need to unlock the bootloader, and root the device. You can then transfer over the USB ROM installation zip file, and the Google Apps (Gapps) package for jellybean. If I can find these, I will attach them to the post for guidance! Ensure you then do a complete NANDROID backup of your device, its better to be safe than sorry. Again, this can be done with the NRT

Next job is to install all your software, I would suggest installing Car Home Ultra first, and then all other software thereafter. I then configured Car Home Ultra to allow 8 shortcuts per page, one media page, and to show compass, date and time, and battery state (See the video below for more clarity). Now I have a nice simple homepage.

Once I had configured the basic user interface, and linked it to each of the programs I wanted it to run, I then started to configure each one in turn. Pairing my Nexus to my OBDII adapter of the car, and to my mobile phone. After this, I was then able to configure both Torque, and Tablet Talk - Allowing me to talk to the car, and anyone I so wish.

Next, was the music player - Installing poweramp, and configuring the media page of Car Home Ultra to use this, now I have the media I want as a minimum.

After this was the configuration of the DAB Radio - Wavesink. You need to ensure its all connected up to the aerial, and then you need to go to the settings, and scan for channels. Job done. You can then click the "back arrow" (per the video) to have a much better user interface...

So now, I have access to the car, my phone, DAB and my own media, along with a friendly user interface to accompany it. Great.


Time to get Physical!

So for the most part, the tablet is almost ready to go, next step, is to get the hardware side of this all setup.

I started by taking off the centre console plastic trim from around the gearstick, this allowed me complete access around the gear lever, and below, then there was removing the main centre console fascia. With all the plastics out the way, I now had the main access I needed, and proceeded to remove the stock radio, leaving in its place, the double din slot.

First job is to install the radio, I ended up going for a deckless stereo, with remote. Connected up the quadlock adapter, and wired that into the new head units wiring, then tapped up the steering wheel controls with one of the Joycon wires. I then had to install a new wire, (I will enclose a basic wiring diagram at a later time to this post!). As the original stereo could tell by the CANBUS that the car was on, the new one didnt work in that way, so I needed a wire to tap into the ignition on of the stereo, so that the signal verified the car was on. This was tapped into the engine sensors.

Now the radio turned on and off with the car. So I wired up the Aerial Splitter. Power was hooked up, and then the cars standard aerial was tapped (ISO to DIN adapter) then into the splitter. Now I can plug in the new stereo to the modified radio, and I still have a separate DAB for a later part. The spare DAB wire was put up at the top of the DIN Space, near the wiring for the switches. I then used the DAB adapter, and hooked it up to my USB RTL2832U adapter, ready for the radio connectivity. All thats left here is to plug it in really.

Next, was running the power. I had at the time of this, a spare 12v I wired in, tucked under the centre console, though I am thinking I am more likely to wire this up to a dedicated switched relay (I have the parts, just need the time!) anyway, I then tap in a 12v extension into this, into one port, I wire in a 4 port USB. This is a basic circuit board, with just four USB ports, All I needed to do was take a 12v wire (cut one off from an old 12v 3 port extension) - positive and negative were then screwed into the USB Board - now I have four ports in a very small space. Great! That will do for powering various small amperage devices.

Next, was to wire in the tablet. In the end, I opted for a two port USB - 12v adapter, plugged in the raspberry PI switched power cable into the 2.1a output. Done. Ran the wire behind the radio area and up to the under switch area at the top of the din.

The hardest part, felt like actually doing the Joyconn EXR stuff. You need a windows PC (I used a windows 10 laptop and a windows 10 tablet). connect up the wire you put in earlier to the stereo controls (in my case, the Grey / Yellow and Blue / Yellow I believe) wiring in the Connector block D. Now, plug the Joyconn into your Windows device. the little light should come on. Now press autodetect on the Joyconn EXR Software. This should detect your switches, when you press up, down, left, right, OK etc the Joyconn screen should show you which reference it ties in with, i.e. A1 to A5. Next job is to tell it which buttons you want it to act as. HINT: The orange buttons on the right hand side are the android options. so click the button A1 on the line, and drag it to (then click) the option on the orange part of the keyboard. I clicked mine so Up, Down acted as volume, Left and right, acted as skip left and right, and OK pressed the "power" button.Click Save and the Joycon Is configured. You can also add long press, though at the moment, I am having issues with this. Next job, wire this in properly, so I took the USB cable, and ran it up to the top of the switches area, above the double din space. 

Now, take the USB adapter you purchased from AliExpress, play with the switch until the blue light comes on with power, and goes off without. I think its position 2. Connect in your USB cables, and the power supply, and you can then connect the car.

So far, I have all the hardware wired in, I took an old tupaware box, and put this under the radio, in the double din slot. All "spare" wiring was tucked in here to keep it as tidy as possible. Next, I attached an IR Repeater to the front of the stereo, powered it via USB and ran the wiring down the passenger side of the console. This will allow me to control the radio and switch it, control master volume, skip FM stations etc etc. I also attached a 90 degree AUX 3.5mm cable to the radio, which will then connect to the tablet.

Now, take the fascia, and mount this in front of the double din space, with the tablet behind. I had to modify mine, to allow the USB cable to come out, so it would still sit flush. Connect up the headphone jack, and the USB cable to the nexus tablet. The device should now power on, if it doesnt, try pressing the power button on the PI power cable, that should do it, if it doesnt work, repeat, whilst setting the switch 1-2-3 to alternative numbers. One of them should work, if it doesnt you have bigger issues to deal with!

Screw the fascia on, and then rebuild the centre console.

You now have a fully functional dash droid.

So far the tablet has the following fully fledged functionality:


⦁DAB Radio through aerial

⦁Internet access

⦁Text Message

⦁Phone Call

⦁Sat Nav


⦁Auto hibernate on power loss

⦁ Backup auto power off if that fails

⦁Auto power on with 12v accessory

Next plans:

⦁Try get hold of a video to WiFi converter, and have the parking cam running to the tablet via wifi. Not a big deal, but it would be a great addition.

⦁Try get TV Working - Not essential, I could (and have) just set Netflix up, Its come in exceptionally useful when motorways have been closed!

Other than that, I still have three seperate ports on my Joyconn, which I can wire in somehow, someway, to automate the tablet even further, I just haven't thought what else would be good yet, one is reserved for the potential future use of my rear view parking camera.


EDIT: I have included below, a crude sketch of my wiring diagram to show how everything is wired up!



Link to comment
Share on other sites

Heres an example video of the dashdroid in action and a few explanations.

I personally think its great, hopefully you do too!

Sadly, video editing is no more my forte than brain surgery!


Link to comment
Share on other sites

  • 3 weeks later...

Well...that's not what I was expecting!! Thought you were going to say "Just call me Jane!"


Nice little project you have going there!!

Be perfect if it could work with the steering wheel controls...

Link to comment
Share on other sites

There are ways to make it work but frankly for the cost of it, it really isn't worth it at the moment sadly. The jpyconn and the likes are about 70 quid!

  • Like 1
Link to comment
Share on other sites

It is entirely possible

It links up to the remote, and counts the resistance for each button press (much as the headunit does!) it then translates that into a keyboard keystroke which can then be mapped to the android tablet.

I thought it would be rediculously expensive, but I just found it for just over £30: http://www.ebay.co.uk/itm/CarPC-JoyCon-Exr-Steering-wheel-controls-USB-interface-/321635437661?pt=LH_DefaultDomain_0&hash=item4ae2f74c5d

To be honest though the worst part is the import taxes if it gets caught in the system, so I have to wonder if its worth while...

But yeah, the tablet runs an app that listens to the keystroke and the keystroke is then translated to an action. For example, volume up can be linked to the bolume up key, down to the down. I could then map he likes of "M" key to an app (so that it opens reverse parking cam for example), left could be treated as a "back" button, and the right button could be used to trigger a home key.

Likewise from what I gather, you can thencreate key sequences, so if I did ... --- ... on the M key, it could translate that to "HOLY FORK" and call 999

  • Like 1
Link to comment
Share on other sites

Loving the sound of the project! All of my Android devices have been rooted and flashed; it makes them so much greater afterwards! I look forward to seeing the work in progress :)

  • Like 1
Link to comment
Share on other sites

Thanks fella. Yeah I'm just awaiting the return of the head unit which is apparently fault free.... Hammer not sure I believe then but ok! Hopefully I can progress this in the next few weeks!

Link to comment
Share on other sites

This sounds amazing! i have searched a few other forums and the possibilities this brings would be great.

I have an android phone but never heard of rooting or flashing until now, safe to say im intrigued!

Link to comment
Share on other sites

Cheers Warren,

Well, I am still on the backfoot at the moment, my stereo was accepted, reviewed and initially they found no issue - then when I told them they need to turn it on and tune it in.... we found the issue!

So they were supposed to be dispatching me a replacement, but since they didnt have that exact model it was a free upgrade to the bluetooth version! so I await eagerly its arrival!.

I found another new app to work with which does the whole interface quite well... Car Home Ultra! seems to do the job quite nicely and fits nicely into place with all my other apps! - Unfortunately TV doesnt work :( I cannot fathom it out, and since I dont have unlimited t'internets I cant get it to work for the foreseeable! and since I dont want to pay £60+ to get a specific piece of hardware and its software, I will do without!

Beyond that, I have narrowed down the issue with the DAB radio, it doesnt work when connected to an extension lead. The good news is, the problem is with the app, as the driver communicates fine with the device and can receive data. The bad news however, is the developers are ignoring my emails and dont seem to want to fix it - so this could be either a job I have to bodge in the short term, or I have to keep harassing the developers to fix it!

Link to comment
Share on other sites

  • 4 weeks later...

Currently at the BETA installation stage (still not setup perfect, but installed sufficiently as proof of concept etc!)

Heres some pictures.

Its got the headunit behind independantly controlled by a remote, (IR Repeater next to the stereo) and the headunit in place. I still have some more wiring to add, but so far, even in its beta phase, I think it looks good, but the jumble of wires on the stereo picture - good job you cant see those...



  • Like 3
Link to comment
Share on other sites

That is one hell of a project but results look good even though it is only temp. Would love to see how it all comes together as i am considering putting my old Samsung tab into my other car like a touchscreen radio etc

Sent from my iPhone using Ford OC

Link to comment
Share on other sites

Will certainly be keeping the thread updated. I also plan on having posts 2 and 3 here as a demo of what it can do and also a tutorial on putting the whole thing together.

Sent from my GT-I9195 using Tapatalk

  • Like 1
Link to comment
Share on other sites

  • 1 month later...

Well, this project is still ongoing. Money is the main reason that its taking quite some time to progress!

Anyway, I have some new parts heading their way to me... a USB switch, so I can choose whether I want to use the general USB devices, or, if I want DAB radio, I can flick to the other USB connector, so thats coming over from China.

I also await a few parts for the aerial, as I need a new base, and I am currently trying to find which DAB / FM splitter I need. I think I have found one, but I then need to convert the "DAB" output connector to my USB device to get the signal.

Anyway, its been sat in the car now, doing its job sweet as a nut! I also managed to find something cheap to try, a specific "DAB to Micro USB TV Aerial" got it for less than a tenner, coming from China (again!) but, that should come with an app that will decode the signals and convert it into plain TV! I dont expect perfection, but its got to be worth a shot!

I cant afford the parking cam to wifi converter at the moment. Currently it costs £40 but I just do not have the money there to spend on it... But that could well be a future release of update on my Dash Droid.

So, by the end of this, I should have extended it to include "TV Coverage" and I can hopefully remove the DAB radio antenna from the back of the car, and have the switch in place to seamlessly flick between the two.

I also have received my means of connecting the steering wheel controls to the android tablet, but to be honest, I dont want to keep stripping the dash down unnecessarily, so I wait for the other parts to come in before I get on with that.

Finally, I have also a new head unit. Its a sony deckless unit, and seems to be a much "cleaner" sound output, however, I so far have not been able to get the RF repeater to work with it, so once it is stuck in the dash, it will be impossible to control, I need to get that working before I can really think about putting it in place.

  • Like 2
Link to comment
Share on other sites

Cheers Paul,

I like the idea of the aftermarket headunit, but to be honest, its just not worth £300+, Right now, I have a radio, I have the android interface, I can work on the likes of the TV, and when I take all into consideration for what I have spent, I cant have spent anymore than about £100 on it, and it should theoretically be an awesome piece of kit!

I will at the end of this update the price list of what it would / did cost!

Link to comment
Share on other sites

  • 2 weeks later...

Thanks chaps. I need to do more pictures when I get the next phases done. Definitely worth it, even the Mrs who wasn't overly happy Mr doing it in the first place is really coming around to the idea of liking it.

Sent from my GT-I9195 using Tapatalk

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...