My In-Dash Nexus 7 Project

[trolley]

Did anyone have any issues with having to remount the USB device when the rom goes into sleep? (turning the car off)

I've been using this setup for a few months now, and it's the only thing that I can't figure out. I've used Tasker to pause music when power is removed, and play music when power is reconnected - but it only plays a few seconds of buffered music before stopping. I have to unmount the external USB via the settings menu, remount, then play the song from the beginning. It's almost seamless, just need to figure out this last step!

Edit: my settings looks exactly like this - http://mehrvarz.github.io/img/usbhost-settings3.jpg

I just reset to factory settings (via recovery mode). Using the default 'Apollo' app, i get the exact same behaviour. Turn car off, music stops. Turn car on, it will play for around 5 seconds, go to the next song for 5 seconds, then stop. The only way I can get the full USB music library back is by unmounting, then mounting the USB device in the 'Devices' page in Settings.

[gradg]

Ok so completed the install yesterday.

The sound difference is absolutely incredible.

My issue,

The unit is showing the charge icon, but just doesnt seem to hold chsrge at all. It works fine charging from a 240v supply in the house. The unit was operating fine last night after the install. All apps etc work.

So the device recognises that its got power from the dcdc, but doesnt hold charge? I cant even run it from ignition now. Its dead flat.

Any ideas? I tried quick charge option also to no avail

[trolley]

I had the same issue and it was one of the apps running in the background that was draining all the power. Go into the Battery section of Settings, see what's consuming all of your power. I think it was Torque Pro? Anyway hit the 'switch application' button and swipe up to close all the apps you don't need.

Agreed about the sound... from Aux in to USB DAC, the difference is like night and day.

EDIT: You'll have to use the power button to turn it back on from flat... I leave my surround half out as I need to use the power button pretty often (too often...), and I can poke my finger back there just enough to hit the button, without pulling the whole unit out.

[gradg]

I had the same issue and it was one of the apps running in the background that was draining all the power. Go into the Battery section of Settings, see what's consuming all of your power. I think it was Torque Pro? Anyway hit the 'switch application' button and swipe up to close all the apps you don't need.

Agreed about the sound... from Aux in to USB DAC, the difference is like night and day.

EDIT: You'll have to use the power button to turn it back on from flat... I leave my surround half out as I need to use the power button pretty often (too often...), and I can poke my finger back there just enough to hit the button, without pulling the whole unit out.

What a PITA. I was under the impression that this PSU should be able to supply enough power to charge and run? Like a normal wall socket can (still only outputs 5V, so whats the difference here?

I turned it back on and it had plenty enough battery, but I'm baffled as to why this DCDC cannot charge this thing enough to make sure it's not going to power down unnecessarily.

To answer your question regarding the USB drive, I've tried it with a flash drive and have not had to do a thing. Works fine, don't need to remount. I'm yet to try it with the HDD.

Anyone else got any handy tips for the settings so it'll charge well enough?

[trolley]

Well the USB connection can only draw so much current to charge at 5V... So it takes a few hours to charge fully. Honestly I assumed it was the apps draining the power - it always happened after i'd used Torque Pro. The ROM should be going into 'deep sleep' which doesn't draw much power, and it shouldn't happen, so i'm clueless.

Thanks for the feedback on the external storage, I need to figure out how to completely wipe and start from scratch. The restore I did is having issues, the bloody screen keeps turning itself off after 2 minutes. LOL.

[gradg]

Well the USB connection can only draw so much current to charge at 5V... So it takes a few hours to charge fully. Honestly I assumed it was the apps draining the power - it always happened after i'd used Torque Pro. The ROM should be going into 'deep sleep' which doesn't draw much power, and it shouldn't happen, so i'm clueless.

Thanks for the feedback on the external storage, I need to figure out how to completely wipe and start from scratch. The restore I did is having issues, the bloody screen keeps turning itself off after 2 minutes. LOL.

I understand that, but that's why in a wall socket charger you've got a step down transformer. They're not outputting 240v, they're 5v chargers. Same as what the DCDC power supply is. I don't want to be pulling the fascia off every time I need to turn it on. I just took a drive and playing music it drained about 5% battery life. Without playing music it barely drained at all, obviously. But I still cannot see how it should drain at all.

I did have an issue with the USB unmounting on me and I had to go back in and re-do the media search.

I also had issues running a HDD from the hub. light on the HDD was on and the drive was spinning, but the nexus didn't want to pick it up.

[seanmau5]

Both issues sound like an amperage issue. When I was bench testing my set up using a 240v wall charger, yes it was outputting the required 5v, however it had nowhere near the required amperage to charge properly and mount the HDD either... Only had around half of the required amperage @ 1.0A

First thing I'd do is check the amperage setting. Did you use 3.0 USB cable? It's needed to support the higher amp output.

[gradg]

Both issues sound like an amperage issue. When I was bench testing my set up using a 240v wall charger, yes it was outputting the required 5v, however it had nowhere near the required amperage to charge properly and mount the HDD either... Only had around half of the required amperage @ 1.0A

First thing I'd do is check the amperage setting. Did you use 3.0 USB cable? It's needed to support the higher amp output.

Are you talking the one that was soldered to the supply from the DCDC?

Amperage setting? As in the jumper on the DCDC?

Thanks for the input sean!

[seanmau5]

Yes, for your power output cables. You need a minimum of 1.8A (1800mA) to fast charge properly.

You also need an OTG cable for the fixed installation setting otherwise you can't invoke fast charging. See picture below - settings under USB HOST - fast charging should be ticked.

[jongyrocka]

For the record....if you anyone feels the need to be running 4.4.4, here is a rom somewhat customised very much like timurs 4.2.2 rom...
I haven't got around to flashing this exact one yet, but I am running something similar (SlimKat), with USB audio patch working etc..

The reason I steered away from Timur's original was simply, because of bluetooth connectivity..I had constant issues trying to connect to my OBDII dongle, and a couple other random things...the behavior was exactly the same when I was running a Cyan Mod on my old Samsung S3....since then, I switched my phone to a Nexus 5, and had noticed my OBDII dongle working 100% with that....so when I put a Slimkat 4.4.3 on N7, it responded the same..100% success rate with the dongle.....

Please note that this is the 3G version...not sure if that has something to do with the whole issue....

I'll be changing up to this rom when I next get an opportunity...


http://forum.xda-developers.com/nexus-7/3g-development/rom-slim-kat-t2826317

On the newer version of powereventmgr you can also customise the timeout before sleep delay (this was a big win for me)

[gradg]

Yes, for your power output cables. You need a minimum of 1.8A (1800mA) to fast charge properly.

You also need an OTG cable for the fixed installation setting otherwise you can't invoke fast charging. See picture below - settings under USB HOST - fast charging should be ticked.

Thanks for the info mate. I have an OTG. Does this too need to be of a specific gauge?

I wasn't even aware that different gauge USB cables existed, I mean I read the part about it in the OP, but was just something I figured was a standard. Oh well.

For anyone looking, I've ordered the Ergotron 97-747 Which is a Type A Male to Type A Female extension with a 28/20AWG, which shouldn't at all have a problem with carrying the power for the charge-in-use. I'll cut it around half way so as I can keep the male end for USB testing at work. So all is not lost.

I'm also gonna add a couple of images that may help with ideas once the setup is permanent:

ODB port is located just above your shin if your foot is on the accelerator. I left this in recently for a week whilst I was away and although it holds a constant 12V there was no issue at all turning the car over to start. (I had read somewhere about people worried about this)

Question: Can the second 5V supply from the DCDC be used to supply the USB hub? I've got a USB hub that works fine with 2 devices in (USB DAC and USB thumb drive) but seeing as the transformer in the 240v plug for the hub (optional obviously) outputs at 5V, can I not just clip the DC plug off it with enough room for the cable and solder that into the secondary 5V supply from the DCDC and have it so that the hub is constantly powered so there's no issue with using HDD and say maybe people charging their phone from it? I can't see why it would be an issue.




I used these fittings I found at bunnings for support of the re-run audio and USB jack on the nexus. Used a small drill to make the holes (I wasn't overly worried about destroying the back of the unit, as I've got a phone and computer that can do all a tablet can, it was purchased only to do this install. Filed the holes out to make a slot for both to fit through and siliconed them to the back of the nexus and also together (the 3 of them). Also used silicone to stick the USB and headphone jack to the backs of the plastic things (not sure what they're even called, found them in the plumbing section.)

I then filled one of them with araldite and put a picture hanger in and bent over the clip to provide a bit of support for the USB charger cable to plug in to. It also gives it something for a small cable tie to wrap around to hold it into place so I'm not ever worried about it popping out. Realistically, it probably wouldn't happen and i've driven it around lately with no issue, but once it's a permanent install with the new supply, I'll be happy to have it secure.


This is where I mounted my DCDC and if you look hard enough, my USBDAC. The USBDAC is mounted on two strips of heavy duty velcro which have been superglued to the back of both the DAC and the crossbar that runs through the dash. No rattles and a strong hold. I can also adjust the output volume from between the vent from here. So it's hidden but works well.
The DCDC unit is mounted with two decent sized thread self-tapping screws to the bracket that normally holds the satnav. These mounting points aren't causing any stress and hold well, and won't pose an issue when I decide to sell and revert to stock. But for now it's a rock solid and stable location.

[seanmau5]

Question: Can the second 5V supply from the DCDC be used to supply the USB hub? I've got a USB hub that works fine with 2 devices in (USB DAC and USB thumb drive) but seeing as the transformer in the 240v plug for the hub (optional obviously) outputs at 5V, can I not just clip the DC plug off it with enough room for the cable and solder that into the secondary 5V supply from the DCDC and have it so that the hub is constantly powered so there's no issue with using HDD and say maybe people charging their phone from it? I can't see why it would be an issue.

Definitely. Alternatively, just make yourself a Y cable for the HDD to draw additional power direct from the power supply. That'll reduce draw on the hub.

[gradg]

Question: Can the second 5V supply from the DCDC be used to supply the USB hub? I've got a USB hub that works fine with 2 devices in (USB DAC and USB thumb drive) but seeing as the transformer in the 240v plug for the hub (optional obviously) outputs at 5V, can I not just clip the DC plug off it with enough room for the cable and solder that into the secondary 5V supply from the DCDC and have it so that the hub is constantly powered so there's no issue with using HDD and say maybe people charging their phone from it? I can't see why it would be an issue.

Definitely. Alternatively, just make yourself a Y cable for the HDD to draw additional power direct from the power supply. That'll reduce draw on the hub.

An option, but it doesn't leave me open to the flexibility that the powered hub will provide

[ShiftyShiv]

Hats off bro great work to Original Post Nexus 7

[Monkey]

Hey guys, I recently bought a 2nd hand surround, vents and cubby for $75 to cut down to fit my Nexus 7 2nd gen (2013). Apart from being cheaper than buying the Japanparts 7" panel kit, I was hoping to use the hinge mechanism from the cubby to create a removable install with the surround opening at the top.

Using a cheap Dremel copy and cutting wheel, I had pretty good results until I discovered that the 2nd gen Nexus is about 10mm too wide to be cut down to fit between the vents, so I kept cutting until I could get it flush but It meant that my vent mechanism had no proper frame and fell apart. So this is basically a forewarning to anyone else attempting it - you cannot modify your existing surround/cubby to fit a 2nd gen 2013 Nexus.

So my question is now, has anyone had success fitting the 2nd gen with the Japanparts panel kit? If yes, can you please post a pic?

Thanks

PS. If anyone wants the left over cubby box and vent tunnels PM me.

IMAG2084.jpg (45.16 KiB) Viewed 4065 times

IMAG2087.jpg (68.2 KiB) Viewed 4065 times