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Aurium
Oct 10, 2010


ratbert90 posted:

No. 5v is what the thing runs off of, and unless the gpio pins are tied directly into the CPU (more than likely 3.3v) You will be fine connecting a 5v source to the pi. I would look at the schematics though to make sure you aren't doing anything stupid like plugging a 5v power source into a 3.3 pin.

They do connect directly to the 3.3v cpu. There is no overvolt protection on the board.

schematic
documentation

HATE TROLL TIM posted:

Okay, can someone clarify GPIO voltage tolerance for me? I keep seeing people say the GPIO is 3v3 only and to never, ever hook 5v up to it or it'll explode. That completely contradicts my experience with it so far.

I picked up a cheap USB to TTL UART adapter from Amazon, based on the PL2303HX chipset.
(Side Note: For $6 it's really nice. Came with a loopback jumper and two sets of leads [M/F+M/M], plus it has 5v and 3v3 outputs for powering small circuits directly!)

I've been using it to console into the RPi for the last week and it's worked flawlessly. I happened to have my multimeter out last night so I decided to see what voltage was going across the TX and RX pins.

Adapter TX --> RPi RX = 5v
RPi TX --> Adapter RX = 3.3v

That got me thinking, so I pulled out an old SR-04 ultrasonic distance module I've had, but never tried to use with the RPi because the echo pin outputs 5v and I didn't think it would work. Wired it up (with a 1k resistor between the echo (output) and GPIO pin to be safe), wrote some quick Python code and it works fine!

So it seems to me the GPIO can handle 5v just fine. Am I missing something?

All your missing is how semiconductors die. If the voltage difference isn't enough to just destroy it right out (by punching though oxide layers and similar) most destruction is caused by overcurrent. Overcurrent generally kills though thermal effects. In short, tiny tiny bits of the chip probably getting hotter than they are speced for, and are (possibly) slowly taking damage.

How long it will last is anyone's guess. It's possible the output and input stage are overbuilt. It's possible they tried to make it 5v tolerant, but the design wasn't robust enough for marketing it as such, but it's still very built up. It's possible your particular chip had some manufacturing variability that improves its resistance. The circuit you have hooked up to it might be current limited enough to never cause a problem. Or it may die tomorrow as the overstressed transistors finally burn out.

You're using it way out of the datasheet specs, and there is just no guarantee about its behavior.

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HATE TROLL TIM
Dec 14, 2006


I see. That makes more sense. I didn't think about a slow death. Though, if I've got a resistor between the data pins, that should current limit it, right? Couldn't I also connect the appropriate sized resistor between the data pin and ground to reduce the voltage? (A resistor divider circuit I guess.)

Rexxed
May 1, 2010

Dis is amazing!
I gotta try dis!



HATE TROLL TIM posted:

Okay, can someone clarify GPIO voltage tolerance for me? I keep seeing people say the GPIO is 3v3 only and to never, ever hook 5v up to it or it'll explode. That completely contradicts my experience with it so far.

I picked up a cheap USB to TTL UART adapter from Amazon, based on the PL2303HX chipset.
(Side Note: For $6 it's really nice. Came with a loopback jumper and two sets of leads [M/F+M/M], plus it has 5v and 3v3 outputs for powering small circuits directly!)

I've been using it to console into the RPi for the last week and it's worked flawlessly. I happened to have my multimeter out last night so I decided to see what voltage was going across the TX and RX pins.

Adapter TX --> RPi RX = 5v
RPi TX --> Adapter RX = 3.3v

That got me thinking, so I pulled out an old SR-04 ultrasonic distance module I've had, but never tried to use with the RPi because the echo pin outputs 5v and I didn't think it would work. Wired it up (with a 1k resistor between the echo (output) and GPIO pin to be safe), wrote some quick Python code and it works fine!

So it seems to me the GPIO can handle 5v just fine. Am I missing something?

It may be worth getting a logic level converter to use your 5v stuff with the 3.3V Raspi:
https://www.sparkfun.com/products/8745
http://adafruit.com/products/395

Longinus00
Dec 29, 2005
Ur-Quan

HATE TROLL TIM posted:

I see. That makes more sense. I didn't think about a slow death. Though, if I've got a resistor between the data pins, that should current limit it, right? Couldn't I also connect the appropriate sized resistor between the data pin and ground to reduce the voltage? (A resistor divider circuit I guess.)

A nice thing to use, even if you're not dealing with voltage differences, are photocouplers aka opto-isolators.

https://en.wikipedia.org/wiki/Opto-isolator

Aurium
Oct 10, 2010


HATE TROLL TIM posted:

I see. That makes more sense. I didn't think about a slow death. Though, if I've got a resistor between the data pins, that should current limit it, right? Couldn't I also connect the appropriate sized resistor between the data pin and ground to reduce the voltage? (A resistor divider circuit I guess.)

While current limiting could potentially prevent damage, you'd never really know what the proper level is, because there really isn't a proper level of current when you're feeding more voltage that it's speced for. There are quite a number of issues that can introduce gotchas in using a series resistor. There are also some concerns about the direct effects of voltage as well. There are circumstances where it is the perfect solution, but really it just isn't recommended.

Voltage dividers are a very common way of doing this conversion. They can cause problems with very high speed signals, but that's not something you need to worry about. The sparkfun board Rexxed linked to incorporates a voltage divider.

As an aside, stepping up from 3.3 to 5v logic rarely has problems. Most 5V logic accepts 3.3v as logic high, so you can just plug a 3.3 logic out into a 5v logic in. It does reduce the margin of operation, and thus reliability, but it does generally work.

DoomTrainPhD
Feb 12, 2009



Yeah I wasn't sure and didn't have time to look at the schematic. Looking at the schematic I am horrified they didn't put at least some overcharge protection on there. Even if that raised to cost to 40$ it would have been worth it.

A c E
Jun 18, 2007

Is this weird? Is this too weird? Do you need to sit down?

Well I had my 512MB rbpi running fine on the main TV, but somehow lost ssh access despite using my normal passwords and needed to mount another share. Combined with the fact that the updates seemed to be causing issues, as I was constantly getting dependency errors for every drat update (for the regular scrapers even). I decided to reload it and set up my older 256MB model on the bedroom TV now that I have a wired connection running in there.

Of course, now I can't get one to work without the other one dying and it's driving me nuts. Both are running Raspbmc, which if either fails again I'm switching to OpenELEC based on the recommendation in this thread alone.

So far I've had:
-System stopped booting after an update
-Display coloured green/purple until I set it up on another tv
-A dead install after a kernel panic after a hard shutdown due to the system not responding
-The system playing half a video, then skipping to the next one each time a video is played
-Another dead boot for no reason.

I've replaced the SD cards and if it was just the one I'd consider it failed, but it can't be both. It wouldn't be so bad if it didn't take so long to scrape all the media.

I'm tempted to try the booting from a network that was posted a few pages back. Everything is wired over a gigabit network and it might save me some grief.

LRADIKAL
Jun 10, 2001
$10


Fun Shoe

are you overclocking? Have you tried different SD cards?

A c E
Jun 18, 2007

Is this weird? Is this too weird? Do you need to sit down?

Jago posted:

are you overclocking? Have you tried different SD cards?

No and yes.

Different types and brands.

Luminaz
Mar 9, 2013

oops !


A c E posted:

No and yes.

Different types and brands.

Have you tried another raspberry pi linux distribution ?

TVarmy
Sep 11, 2011

like food and water, my posting has no intrinsic value



Also, have you tried different power supplies?

A c E
Jun 18, 2007

Is this weird? Is this too weird? Do you need to sit down?

Luminaz posted:

Have you tried another raspberry pi linux distribution ?

Not recently, but I will switch if either one has issues again.

Yes to the power question.

Luminaz
Mar 9, 2013

oops !


I love my raspberry pi. I used it in combo with xbmc and my harmony remote. It works well with an IR receiver. It's definitly a must have !

LRADIKAL
Jun 10, 2001
$10


Fun Shoe

Ace, maybe you ought to return that thing as defective?

Clamlapper
Oct 26, 2010


ratbert90 posted:

Yeah I wasn't sure and didn't have time to look at the schematic. Looking at the schematic I am horrified they didn't put at least some overcharge protection on there. Even if that raised to cost to 40$ it would have been worth it.

There's no point adding $15 worth of protection to a $25 piece of equipment. If you destroy it, just buy a new one.

The whole point of the device is make something cheap and disposable. Something kids and adults can play with and break. It isn't in anyway intended as a robust piece of consumer electronics.

Clamlapper fucked around with this message at 11:26 on Mar 12, 2013

A c E
Jun 18, 2007

Is this weird? Is this too weird? Do you need to sit down?

Jago posted:

Ace, maybe you ought to return that thing as defective?

I have 2. They both seem to be working fine currently so I'm just going to leave it for now, but it was a very frustrating two day.

deong
Jun 13, 2001

I'll see you in heck!


Does anyone have a recomendation for a good remote/keyboard for OpenELEC?
I was looking at iPazzPort Mini Wireless Fly Air. I didn't see an OpenELEC specific review, but I did see that it works with RaspXBMC minus some key mappings. So easy enough to get around.

Basically I'd like to get a remote that's like the Boxee remote if possible. With a touch pad would be cool.

Luminaz
Mar 9, 2013

oops !


deong posted:

Does anyone have a recomendation for a good remote/keyboard for OpenELEC?
I was looking at iPazzPort Mini Wireless Fly Air. I didn't see an OpenELEC specific review, but I did see that it works with RaspXBMC minus some key mappings. So easy enough to get around.

Basically I'd like to get a remote that's like the Boxee remote if possible. With a touch pad would be cool.

If you want to use it with an universal remote, I use this one Hama MCE Remote with my Harmony.
The only configuration I have to do is to learn some commands with the original remote. But everything else works fine.

deong
Jun 13, 2001

I'll see you in heck!


Luminaz posted:

If you want to use it with an universal remote, I use this one Hama MCE Remote with my Harmony.
The only configuration I have to do is to learn some commands with the original remote. But everything else works fine.

I don't have a universal remote currently, and really don't need one. I only have the tv (no receiver, DVD, etc) and it seems like that'd be a more expensive way to go. I'd like to have something with a keyboard for linuxing around. I'm planning on using BerryBoot to play around with different OSs/services.

Photex
Apr 6, 2009






anyone using this with Rasplex yet? I find that Plex is a great backend even for XBMC.

KrautHedge
Dec 5, 2008


Photex posted:

anyone using this with Rasplex yet? I find that Plex is a great backend even for XBMC.

I tested it out a few weeks ago. Interface was extremely slow, and the whole thing crashed during playback. It seemed unusable at that time.

Luminaz
Mar 9, 2013

oops !


For the moment I think that xbmc is the best media center solution for raspberry pi. But it's nice to see that other software can be adapted to it.

AgentF
May 11, 2009


AgentF posted:

Raspberry Pi thread, help me! I can't get my Pi to output HDMI to my TV.

- The TV is a Sony Bravia KDL46ex520
- The Pi outputs through the composite port when connected to the TV
- The Pi outputs HDMI perfectly when connected to a HDMI monitor
- hdmi_safe doesn't help, neither does hdmi_boost
- I've tried countless combinations of hdmi_group, hdmi_mode
- When I try hdmi_force_hotplug, the composite won't output and the TV changes to the correct HDMI channel but still doesn't display anything

I am desperate for ideas at this point. What can I try next?

Edit: Discovered my power source was providing only 4.4V. Found one that provides 5V. Now the TV recognises the input as coming from "Player 1(raspberrypi_li)" but still won't display HDMI.

Hi RaspberryPi thread. Now that I've got free time again I've gone back to trying to get my Pi to work. Since I made this post I've done an experiment where I connect the RaspberryPi to the HDMI monitor and get it to display the desktop, and then unplug the monitor from the Pi and connect the TV lead to it. The result is that the TV acts as it did before, it won't display the picture or recognise the HDMI connection. When I connect the Pi to the monitor, the monitor displays the desktop again. For clarity, I should note that it is a DVI monitor with a HDMI-to-DVI cable, and not a natively HDMI monitor.

Does anyone have any hints on what I can try to get my Pi working with the TV? The fact that it works fine with the monitor, and that a second RaspberryPi exhibits the exact same behaviour, makes me think that my TV isn't performing it's responsibilities for the HDMI connection somehow. Does anyone know the particulars of how a HDMI connection is established between devices?

HATE TROLL TIM
Dec 14, 2006


Out of curiosity, have you tried another HDMI cable from a different manufacturer? Perhaps take the one off your game console / set top box and try it? A lot of HDMI cables take shortcuts by not providing unique grounds for all the data lines.

AgentF
May 11, 2009


I don't have another cable but I think I can borrow one and give it a try. This cable seems to work fine for connecting a laptop to the TV but maybe those are more tolerant than RPis?

Hed
Mar 31, 2004



Fun Shoe

Yeah I had a Sony TV that didn't work with one of my HDMI cables (a decent Monoprice one at that) but switching it out fixed it. Never noticed any problem on my Samsung but I never tried the Pi on it either v v

porktree
Mar 23, 2002

You just fucked with the wrong Mexican.


AgentF posted:

I don't have another cable but I think I can borrow one and give it a try. This cable seems to work fine for connecting a laptop to the TV but maybe those are more tolerant than RPis?

Sounds to me like the TV isnít sensitve enough to detect the signal from he Pi. I had an Insignia that wouldn't see my bluray player on start up, had to cycle the player to get it detected. In other words the digital signal isnt high enough to hit the hdmi input detection levl of your TV.

AgentF
May 11, 2009


I figured hdmi_boost is designed to overcome a lack of sensitivity to HDMI? Maybe I'm not supplying my RaspberryPi with enough power?

AgentF
May 11, 2009


New cable seems to have done the trick! Time to start playing with my Pi ! Thanks for the suggestions everyone!

HATE TROLL TIM
Dec 14, 2006


Speaking of displays... Got my Lapdock going last night! I ended up cutting the end off an HDMI cable and wiring it directly into the JHDMI connector on the Lapdock's mainboard. I decided having a 1m cable pair coming out of the back would be the ideal setup for me, versus having connectors on the Lapdock itself. Plus I don't have to wait 3 years for the micro-HDMI gender changers to get here from China!





Now I've just got to get that all bundled up and tight, then move on to the USB.

HATE TROLL TIM
Dec 14, 2006


Got it finished tonight!







The last picture shows how the HDMI cable is now hardwired in, while I retained the OEM micro USB male connector. That plugs into a short micro USB female to USB A female adapter. There's also a small wire pair running out that's connected together with simple crimp-on interlocks; this is the DDC/CEC ground which serves as a makeshift power switch. There's a small steel pin running through where the "dock" unit used to be that I've anchored the cables to for straight relief support.

So right now power and data is fed to the RPi over a single full sized USB male to male cable and video and sound are handled by the full sized HDMI connector.

Works amazingly well. $70 well spent!

Katana Gomai
Jan 14, 2007

"Thus," concluded Miyamoto, "you must give up everything you have to be my disciple."



I've been looking for the cheapest way of getting twitch.tv onto my TV and stumbled across the Pi; apparently there's even a twitch.tv plugin for XBMC. How is the Pi doing with regard to MKV playback etc.? I'd probably just slap an external HDD onto it and use it as a proper media server if I'm making the effort of buying it as a twitch-machine but I'd like to know whether it can output 1080p video beforehand.

Lukano
Apr 28, 2003



Yeah it plays 1080p mkv's just fine.

KetTarma
Jul 24, 2003

Suffer not the lobbyist to live.


Looks like my tax return is going to give me sufficient reason to set up another pi. This one is going to be one of those HTPC builds that I hear so much about. Hooray!

Benson Cunningham
Dec 9, 2006

Chief of J.U.N.K.E.R. H.Q.


I just ordered a raspberry pi. My ultimate goal is to put together an arcade cabinet with it. What I'm stuck on is the hardware aspect of that.

I'm looking at this for my joystick: http://www.adafruit.com/products/480

Is there a good tutorial somewhere that can take me from having a joystick to registering the input on my pi? I have no background in electrical engineering, so I am really at a loss as to what I need to do on the hardware side. Can I wire the joystick outputs directly to the GPIO and just configure an emulator to accept signals from the GPIO? Do I need a breadboard? What other hardware do I need (wires, breadboard, etc) to get it up and running.

Or do I need to step back, and get some kind of foundation in electrical engineering so I can understand what's going on?

Gism0
Mar 20, 2003

huuuh?

gently caress you Raspbmc: http://www.raspbmc.com/2013/04/crac...dware-decoding/

I hate april 1st.

armorer
Aug 6, 2012

I like metal.

Benson Cunningham posted:

I just ordered a raspberry pi. My ultimate goal is to put together an arcade cabinet with it. What I'm stuck on is the hardware aspect of that.

I'm looking at this for my joystick: http://www.adafruit.com/products/480

Is there a good tutorial somewhere that can take me from having a joystick to registering the input on my pi? I have no background in electrical engineering, so I am really at a loss as to what I need to do on the hardware side. Can I wire the joystick outputs directly to the GPIO and just configure an emulator to accept signals from the GPIO? Do I need a breadboard? What other hardware do I need (wires, breadboard, etc) to get it up and running.

Or do I need to step back, and get some kind of foundation in electrical engineering so I can understand what's going on?

I built an arcade unit with a raspberry pi. If you can't solder, it is going to be a huge pain in the rear end at best. If you can solder, then it is fairly trivial to wire everything up. There is full support for interfacing with two SNES controllers via the GPIO pins. (Check out RetroPie, and the gamecon-gpio-rpi driver). I bought two 3rd party SNES controllers, dismantled them to get at the underlying circuit board, and soldered connectors directly to the button contacts. Then I ran a wiring harness from those connectors out to the arcade controls (which I bought from https://arcadespareparts.com). This resulted in me having two player arcade controls that looked like two SNES controllers to the RPi, and thus worked perfectly with the gamecon-gpio-rpi driver.

Skills needed: soldering (lots of damned soldering), comfort at the linux command line, patience.

Benson Cunningham
Dec 9, 2006

Chief of J.U.N.K.E.R. H.Q.


Thanks! I have never soldered before but I can buy the stuff if I need to. I was looking at the ipac2 also- http://www.ultimarc.com/ipac1.html. I was just considering it because it might simplify things for me to be able to connect via usb and still have my GPIO ports available.

I'll let you know which way I end up going. From some additional reading I did online it sounds like a lot of people buy pc controllers and just crack them open for the boards.

Mill Town
Apr 17, 2006



Rather than cutting up a SNES controller, you can build the equivalent circuit out of two easy to obtain microchips:

http://www.gamesx.com/controldata/nessnes.htm

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armorer
Aug 6, 2012

I like metal.

Mill Town posted:

Rather than cutting up a SNES controller, you can build the equivalent circuit out of two easy to obtain microchips:

http://www.gamesx.com/controldata/nessnes.htm

Excellent. I knew that was an option but I built the thing in about a week to use as a prop in a talk, so I went with the easy approach I could buy on amazon. Thanks for the link though, I plan to build a coffee table style unit in the near future and I will use those.

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