There are many of us in the Nexus 7 community who are looking to build our tablets in to our cars and other places where the power button will not be practically accessible. I am one of those people. I was wondering if anybody had any ideas on how to extend the power button?
The ribbon cable for the power and volume buttons can be seen here: http://www.ifixit.com/Guide/Installing+Nexus+7+Power+&+Volume+Button+Cable/9926/2
The header/connector on the board for the cable looks way too small to solder to and so my latest idea is finding a replacement ribbon cable that I could extend in to a tiny gauge wire and externalize from the case. From what I've been able to find so far, I think this is a ZIF FPC/FFC type ribbon cable and connector? I was thinking of something like this: http://www.mouser.com/ProductDetail...GAEpiMZZMvyL%2b65tEJ/L29YMZjxdjhiuZuU4IfHbXs= But I truly have no idea if this cable will fit? Anybody who's great with PCBs who would like to chime in?
If it helps I found a Molex catalog that has a couple connectors that look similar:
http://www.molex.com/catalog/web_catalog/pdfs/F.pdf
Subscribed!!
Ive been considering the nexus for my car pc aswell. Once i pick mine up i will tear it down and see if a ribbon cable could be either extended or possibly simply cut and have wires soldered to it for external power and volume. I have already designed a power supply for the nexus in the car that would also power a DAC and a HDD. I can provide the part number for the TI power chip that i used if anyone is interested. Its capable of producing 6 amps of current at 5 volts.
physical buttons suck. make all phone with only capacitive buttons,.
Interesting
jllbenson said:
physical buttons suck. make all phone with only capacitive buttons,.
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How would that make externalizing the buttons as needed in this application any easier..?
irishboym4 said:
Ive been considering the nexus for my car pc aswell. Once i pick mine up i will tear it down and see if a ribbon cable could be either extended or possibly simply cut and have wires soldered to it for external power and volume. I have already designed a power supply for the nexus in the car that would also power a DAC and a HDD. I can provide the part number for the TI power chip that i used if anyone is interested. Its capable of producing 6 amps of current at 5 volts.
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This is what I ended up doing. I got some good advice from another XDA'er who suggested I just pop the bubble button off the ribbon and solder to the contacts directly. In reality the bubble buttons are on a laminated sticker that I could just peel back. Then I soldered to the pads and pushed the cables out through where the rubber for the power button used to be. So far things seem to be working well, I'm a little weary of how this soldering will survive the swings in temperature being left in the car, but I guess there's only one way to find out. Observe:
dmexs said:
How would that make externalizing the buttons as needed in this application any easier..?
This is what I ended up doing. I got some good advice from another XDA'er who suggested I just pop the bubble button off the ribbon and solder to the contacts directly. In reality the bubble buttons are on a laminated sticker that I could just peel back. Then I soldered to the pads and pushed the cables out through where the rubber for the power button used to be. So far things seem to be working well, I'm a little weary of how this soldering will survive the swings in temperature being left in the car, but I guess there's only one way to find out. Observe:
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Thats very nicely done. I want to do power and volume for my setup. Did the wire size you use work well or would you recommend smaller? otherwise i will need a separate volume control solution for the system. what do you have your tablet connected to for your amp and speakers?
Thanks. I used a 22 gauge wire, the smaller the better I think, as long as it's not bare. As far as amp, I'm using an aftermarket CD deck with a 3.5mm audio in. So I don't really plan on changing the volume on the tablet itself. I'll probably just keep it at 90% to avoid clipping and then adjust the gain with the CD deck. I haven't put it in my car yet though.
Steering Wheel Controls for Car PC
Has anyone tried the Joycon steering wheel control system with an android yet? It supports HID and no drivers are required for windows. It says that it cannot be programed from a linux or mac computer but just windows. Though once its programed it can be used with linux. Im thinking USB OTG plus this guy and you could control the tablet right from the steering wheel.
The solder will last fine on that job. The only thing I would be concerned about is getting false "presses" from the one lead that's soldered to the middle touching the outside ring. Perhaps just place a piece of electrical tape under it. Your other option might be to go straight from the connector the the flex plugs into. Just use a multimeter to test which pins you need to tap.
Thank you so much.
dmexs said:
How would that make externalizing the buttons as needed in this application any easier..?
This is what I ended up doing. I got some good advice from another XDA'er who suggested I just pop the bubble button off the ribbon and solder to the contacts directly. In reality the bubble buttons are on a laminated sticker that I could just peel back. Then I soldered to the pads and pushed the cables out through where the rubber for the power button used to be. So far things seem to be working well, I'm a little weary of how this soldering will survive the swings in temperature being left in the car, but I guess there's only one way to find out. Observe:
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I just wanna thank the hell out of you. I have been searching and measuring that tiny little cable for about 2 hours now trying to find a connector and cable the right pitch/pins. Somehow the magical world of google brought me here. A site, despite my post numbers, I frequent very often. I'm installing the tablet in my car as well and I too needed a solution to the power button. Cant believe I didnt think to check here. You posted this just a few days ago. Crazy. Once again thank you. I should be able to pull this off no problem.
---------- Post added at 07:55 AM ---------- Previous post was at 07:49 AM ----------
Oh and by the way any issues with this so far? I dont imagine you have seeing as a switch on the to ends of the wire are doing exactly what the little foil button does. Just wanted to ask though before I commit to this in a couple of days.
I recommend if you are going to put it in a car, it needs some sort of quick release. If any stress is put on that cable, the contacts would either lift or the flex would rip pretty easily. I did my nook soldered straight to the main board and a quick release in the cable between the board and the button. I also did as much as I could to keep the cable from the back housing to board from moving by putting tape and locking the cable down when I put the back housing on.
The first picture shows the main board of the Nook. I just took off the old button and replaced it with my wiring. I used hot glue to keep it from wiggling.You can see the quick releases I used in the second picture. I just pulled them from a donor PC I had laying around.
Being a USB fan, I'd try to see if a custom USB device could do the job.
Just recently I made a USB volume control for Windows.
It works on my Nook Touch too.
Omyn said:
I recommend if you are going to put it in a car, it needs some sort of quick release. If any stress is put on that cable, the contacts would either lift or the flex would rip pretty easily. I did my nook soldered straight to the main board and a quick release in the cable between the board and the button. I also did as much as I could to keep the cable from the back housing to board from moving by putting tape and locking the cable down when I put the back housing on.
The first picture shows the main board of the Nook. I just took off the old button and replaced it with my wiring. I used hot glue to keep it from wiggling.You can see the quick releases I used in the second picture. I just pulled them from a donor PC I had laying around.
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Exactly. I'm planning on using a male and female molex connector I found at radioshack. Currently I'm trying to figure out some intricacies involving Google Music and external storage but soon I'll have more pictures up here.
dmexs said:
Exactly. I'm planning on using a male and female molex connector I found at radioshack. Currently I'm trying to figure out some intricacies involving Google Music and external storage but soon I'll have more pictures up here.
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keep us posted on the google music + external storage because i will be doing that soon aswell.
Have you tried connecting a faux USB HID device (like the Arduino Leonardo) and sending arbitrary keycodes while it's "off" to see whether any might be capable of waking it up? I don't know whether that could power it up from a "cold off" state, but I'm 99% sure you could wake it up from "screen off, asleep" that way.
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bitbang3r said:
Have you tried connecting a faux USB HID device (like the Arduino Leonardo) and sending arbitrary keycodes while it's "off" to see whether any might be capable of waking it up? I don't know whether that could power it up from a "cold off" state, but I'm 99% sure you could wake it up from "screen off, asleep" that way.
Sent from my SAMSUNG-SGH-I747 using Tapatalk 2
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I haven't tried this. I've just been using my externalized power button to wake the device from both warm and cold off states. I have a CNX-2140 power supply from my old car PC setup that has an ACPI pulse. I use this to wake the device from a warm sleep.
Thanks you XDA for being here. Just solved half of the problem my friend was having for his tablet . Mounting it in a 2006 Mustang. Now, Gotta see if he can use the POGO for charging and a USB OTG for the external camera
its help!! thanks!
What do you terminate the raw wire ends to now? I'd by looking at mounting some kind of button inside the cab of my vehicle to turn it on/off. What kind of button would a person look for? Thanks
---------- Post added at 09:44 AM ---------- Previous post was at 09:39 AM ----------
dmexs said:
How would that make externalizing the buttons as needed in this application any easier..?
This is what I ended up doing. I got some good advice from another XDA'er who suggested I just pop the bubble button off the ribbon and solder to the contacts directly. In reality the bubble buttons are on a laminated sticker that I could just peel back. Then I soldered to the pads and pushed the cables out through where the rubber for the power button used to be. So far things seem to be working well, I'm a little weary of how this soldering will survive the swings in temperature being left in the car, but I guess there's only one way to find out. Observe:
Click to expand...
Click to collapse
What do you terminate the raw wire ends to now? I'd by looking at mounting some kind of button inside the cab of my vehicle to turn it on/off. What kind of button would a person look for? Thanks
I cracked my screen and replaced the screen, digitizer, and frame. Before replacing it the power button worked fine, in fact turned on just before I got the case off annoyingly. Replaced all the parts, made sure the power button pcb was in place, and charged the battery which causes the screen to light up. But now the power button is not turning on the phone. I'm a bit confused, it feels like its hitting the button. Wonder if anyone has run into this problem when tearing apart there phone and putting it back together? I'm going to check the power button pcb again, and try to power it up with the back off.
Edit: Torn it apart again, checked the power PCB board with my multimeter and I have continuity when the button is pressed. Made sure the power button is touching the logic board to. I starting to think my logic board got fried when I torn it apart. Would the logic board be fried if the screen still lights up when you plug in a charging cable?
Solution: Figured it out. The bent contact pins that touch the logic board 1 had been bent to much in while disassembling and reassembling so it wasn't actually touch the logic board. Couldn't see it till I could the tiny power pcb board out.
Also figured out how I bent it. When you take the black plastic cover off the logic board the clip on the left side is a bit tricky to get off. The only good spot to get under the cover is right next to the power board, and I happen to wedge my pry tool at some point between the logic board and the pin on the power PCB. I also found out I did the same thing on the volume PCB for volume down. So just an FYI to watch out for that when taking this thing apart.
what I have:
A single wire from my apart wall, that connects to the door button, when I use multimeter, it reads 0V - 0.5V AC, when someone press the door button, it raises to 5V AC
I have no access to the door buzzer transformer, and I don't konw when it's isolated or floating or even has a ground
a RPi 2B, some resistor, some capacitors, some sharp817 optoisolators, a breadboard, some jumper wires
What I want to do:
I want to connect this wire through an optoisolators and resistors to the RPi's GPIO, so I can call something like
GPIO.add_event_detect(channel, GPIO.RISING, callback=my_callback) to detect the door button push event
What's my problem:
I have no idea how to exactly make the cirecuit work, especially there is only one AC wire (positive live wire may be?, where's the ground wire?)
please help
and wish everyone merry christmas
I think it would be easier, when you use a schmitt-trigger and control a digital input of the Rpi. Did i understand right, that you only want to detect 0V or 5V ? You are not interestet in voltage levels between ?
Hey guys,
My brother installed a Nexus 7 into his dash and soldered wires onto the power ribbon cable similar to what Bossman137 did. He attached a toggle switch to this but I'd like to replace it with an illuminated momentary switch similar to this. I'm aware the switch will need power to light the LED but I'm unsure how I'd wire this.
It seems that on older headunits soldering job is done very bad and much of mentioned and not mentioned problems are solved by resoldering android board.
Symptoms can be :
- not working backlight,
- not working gps or no satelites found,
- not working wifi,
- device not powering off or tuning screen of when you take key out from ignition, instead staying powered on for few or more minutes,
- switching to reversing camera by itself,
- not powering on,
- and many other....
Device should power off in very little time when you take key out if it is connected properly and by properly I think on supplied connectors and all wires connected, usually there are 3 wires black, yellow and red, black should be ground, yellow positive and red positive but switched on when you start your car and off when you take key out of ignition.
To fix most of the problems in all my cases you simply need to resolder all pins on android board which is soldered on top of main board, here are some photos and one very important video:
On photo you can see what you need to resolder, and yes you need to do it all and need to use leaded soldering wire and bunch of soldering flux.
Video: you should look whole but pay special atention on the part starting from 1:53 that is technique you need to use to do a good resolder job:
And last you should loose top cover of your head unit and replace it with big quiet fan which you can connect on mentioned black and red wire which will power the fan when you start the car and make things work better.
Atached is photo of my 5min job of zip tie mounted and not protected fan, but you should use grill taken from pc power supply or some other whey of preventing wires go into fan and making very nice sound and smell of shreded wires.