Automotive application assistance required

Moderators: meveric, mdrjr, odroid

Automotive application assistance required

Unread postby alltracfreak » Wed Feb 03, 2016 5:58 pm

Hello everyone im looking into getting either a c1+ or xu4 And will be using the 7inch odroid screen in place of my factory gauge cluster. Do i need a dc to dc step down transformer so i can wire it directly into the cars electrical system. And is their a way i can have it skip boot up and go directly into an app when power is applied and can it auto shutdown when power is removed?
alltracfreak
 
Posts: 2
Joined: Wed Feb 03, 2016 5:05 pm
languages_spoken: english

Re: Automotive application assistance required

Unread postby rooted » Wed Feb 03, 2016 6:58 pm

Yes I would step down the voltage for safety.

Not exactly the way you describe unless your UI will run on a framebuffer.

You will need to design (or purchase) an existing solution to support smart shutdown like that.

Or risk data corruption and just shutdown by removing power.
User avatar
rooted
 
Posts: 3673
Joined: Fri Dec 19, 2014 9:12 am
Location: Gulf of Mexico, US
languages_spoken: english
ODROIDs: C1
C1+
C2
XU3 Lite
XU4
VU7+
HiFi Shield 2
Smart Power (original)

Re: Automotive application assistance required

Unread postby odroid » Wed Feb 03, 2016 7:09 pm

There are a few system apps to enable the auto-start an application.

Refer this link as an example of step-down power board.
viewtopic.php?f=97&t=14988&p=123426#p123414
User avatar
odroid
Site Admin
 
Posts: 25323
Joined: Fri Feb 22, 2013 11:14 pm
languages_spoken: English
ODROIDs: ODROID

Re: Automotive application assistance required

Unread postby alltracfreak » Wed Feb 03, 2016 11:52 pm

Sweet thanks! What kind of solutions do they have for the autoshut down? Im brand new to the single board world and really dont know how to do anything but could learn.
alltracfreak
 
Posts: 2
Joined: Wed Feb 03, 2016 5:05 pm
languages_spoken: english

Re: Automotive application assistance required

Unread postby odroid » Thu Feb 04, 2016 11:19 am

Voodik's Android 6.0.1 Marshmallow for ODROID-XU3/XU4 recently supports the simple shutdown feature.
viewtopic.php?f=94&t=17712&start=50#p121064
User avatar
odroid
Site Admin
 
Posts: 25323
Joined: Fri Feb 22, 2013 11:14 pm
languages_spoken: English
ODROIDs: ODROID

Re: Automotive application assistance required

Unread postby Eamonn » Thu Jun 09, 2016 10:57 pm

I know this is an old thread, but I did the same so I thought I'd post in case someone else has similar thoughts or questions. There are a few ways to do this but I implemented an automated hardware turn on/off function through a simple hardware circuit with some software modifications to Voodik's excellent OS. Tasker and WiringPi are two great pieces of software that are well worth looking at if you have the shifter board and want to do the same. Here are some simple tips to point you in the right direction:
A car starts off of a 12V battery. When the engine is running the alternator brings this voltage up to 14V in order to keep the battery charged. The XU4 runs off of a 5V 4A supply so a DC-DC converter will be required that can accept an input voltage swinging between 11-13 volts DC and O/P a stable 5V DC up to 4A. My XU4 runs at an average of about 1.6A but can draw down more current if more USB devices are connected or the processor starts chewing up heavy code. Most cars have 2 important wires going to the cars head unit that you can splice into: 1 = Bat+ which is a direct connection to the battery positive terminal passing via the fuse box and is always live. 2 = Vcc which only goes live when the key is in the ignition and is turned to the on position. The chassis is always grounded so it is always connected to the battery's negative terminal. Because the chassis is always connected to the battery terminal that means every piece of metal has a connection back to the battery - so unplug the battery when cutting wires and ALWAYS use a fuse in series with the + power going to your odroid device. The last thing you want is for a + wire to accidentally come in contact with any metal surface and start an electrical fire in your car when you are doing 120. Hardkernel wont be responsible if your project or you go up in smoke.
Also for audio please be aware that you will need an audio amplifier to power your cars speakers. A USB sound card doesn't have anywhere near enough juice to do this and outputs about 0.25W max (depending on the USB device). Personally I upgraded my speakers and ran the XU4 audio through 2 amps giving a total of 1300W RMS, 2800W max. But I'm crazy and had too much free time. :D :D
Eamonn
 
Posts: 24
Joined: Thu Aug 13, 2015 5:47 am
Location: Ireland
languages_spoken: English, Dutch, German, Russian
ODROIDs: XU4, C1+, C2


Return to Android

Who is online

Users browsing this forum: No registered users and 2 guests