I'm trying to make my first Raspberry Pi to run a script that uses files from memory cards. Since my Pi does not have a display I want to write it in a fail safe way where it does not matter if somebody pulls the card at any time. Now I'm just wondering what the best way would be. I'm talking about multiple adds and removes of usb sticks per run. The card will be read only.
How would you solve that?
Would you stick to fstab or rather use python to auto mount after detection over dbus?
What kind of clean up is necessary after a volume has been pulled out of the usb slot?
Jason, if you use a automount, and define a short commit time on automount configuration, the removal of flash card is secure.
I use "usbmount" service.
My especific config (at /etc/usbmount/usbmount.conf) is:
FS_MOUNTOPTIONS="-fstype=vfat,umask=000,commit=1 -fstype=ext4,commit=1,relatime"
with define a time of 1 second to start to write on flash card.
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I'm excited. I'm a long-time lurker here at SO, but I've never posted. Here goes!
I'm trying to develop a device that would connect to a host RPi through (preferably) USB, and would have multiple 3.5mm jack outputs. The goal, ultimately, is to get the device to use a standalone program that, when a button is pressed (keyboard, or other external input), a specific sound (or set of sounds) would go through a single 3.5mm output. Now, I understand that there's going to (most likely) have to be an external box, and I also realize that I'm in above my head, but I'm trying to create this as more of a hobby and as a learning experience.
Basically, the way it would go is that the user would set which inputs triggered which outputs beforehand on the custom software in the RPi. The input would then trigger that ouput then await a new signal. I figure I'm going to need to also build a physical box to house the amount of 3.5mm jacks I want (i figured 3-5.)
So, where do I need to start? I don't need a guide on how to do this, more of a step in the right direction. From what I can discern, there's not anything out there that does this. If there is, please show me and I'll get that instead. I've done a lot of googling on this, and I'm thinking that I'll use Raspbian on the Rpi, and code the software using Python. I know I'll also need to build a driver so that the external box and the RPi can communicate. Lastly, I assume that I'll need some type of circuitry for the external box. That's where it gets hairy to me. I've never dealt in physical I/O except for a bit of modding. Where would I start my search there?
Any help at all is appreciated, and thanks for reading this huge post. Thanks!!!!!!!!!!!!
Is it possible to get the system output audio (the exact same thing that goes through the speakers) and analyze it in real time with Python? My intention is to build a sound visualizer. I know that it is possible to access the microphone with pyaudio, but I was not able to access the sound card output in any way, I'm looking for a solution that works on Windows.
Thank you for reading.
Not sure how this project is doing these days, it's been a long time since it's been updated. PyVST allows you to run python code in a VST inside a VST host, which makes it possible to handle realtime audio events.
You might want to look at http://code.google.com/p/pyo/ for some ideas about how to handle DSP data as well.
So I have tried to find a answer but must not be searching correctly or what I'm trying to do is the wrong way to go about it.
So I have a simple python script that creates a chess board and pieces in a command line environment. You can in put commands to move the pieces. So one of my co workers thought it would be cool to play each other over the network. I agreed and tried by creating a text file to read and write to on the network share. Then we would both run the script that reads that file. The problem I ran into is I pretty much DOS attacked that file share since it kept trying to check that file on network share for a update.
I am still new to python and haven't ever wrote code that travels the internet, our even a simple local network. So my question is how should I go about properly allowing 2 people to access this data at the same time with out stealing all the network resources?
Oh also im using version 2.6 because thats what everyone else uses and they refuse to change to new syntax
You need to use the proper networking way. It's not quite hard for simple networked program like yours.
Use the one from the Python's stdlib http://docs.python.org/library/socket.html (also take a look at the examples at the bottom of the page).
First off, without knowing how many times you are checking the fle with the moves, it is difficult to know why the file-share is getting DoS-ed. Most networks and network shares these days can handle that level of traffic - they are all gigabit Ethernet, so unless you are transferring large chunks of data each time, you should be ok. If you are transferring the whole file each time, then I'd suggest that you look at optimizing that.
That said, coming to your second question on how this is handled at a network level, to be honest, you are already doing it in a certain way - you are accessing a file on a network share and modifying it. The only optimization required is to be able to do it efficiently. Even over the network operations in a concurrent world do the same. In that case, it will be using fast in-memory database storing various changes / using a high-scale RDBMS / in the case of fast-serving web-servers better async I/O.
In the current case, since there are two users playing the game, I suggest that you work on a way to transmit only the difference in the moves each time over the network. So, instead of modifying the file over the network share, you can send the moves over to a server component and it synchronizing the changes locally to the file. Of course, this means you will need to create a server component that would do something like this
user1's moves <--> server <--> user2's moves . Server will modify the moves file.
Once you start doing this, you get into the realm of server programming / preventing race conditions etc. It will be a good learning experience.
I would like to know if there are any API's for python to programmatically control a phone, like starting and ending calls, but also to record conversations.
I would also like to use the Headphones and Mic of the computer to talk over the phone.
Any info would be great, I tried googling for something, but nothing useful came up.
Be careful when using PyBluez! The results will actually depend on the BT-USB dongle you are using. Depending on the hardware(the BT chip in there), PyBluez will use one or another BT stack - for example there was one from WIDCOMM. Results will vary, as PyBluez is actually wrapping around those stacks - all of which are far from complete.
So, when you have a working project, be sure to know what actual BT stack you were using :)
For Python audio stuff, you could try this.
PyBluez is an effort to create python wrappers around system Bluetooth resources to allow Python developers to easily and quickly create Bluetooth applications.
Unfortunately I've not found a page dedicated to its features, but it could be a good starting point, whether everything you need is in its feature set, or if you could build your application upon it by extending it.
http://code.google.com/p/pybluez/
When an audio or midi clip is played (triggered), its name needs to be sent using OSC to another application.
LiveAPI is an interface which allows one to explore and automate Ableton Live using python scripts.
The code to do this must be written in a python script, which must be placed in a specific folder where Ableton Live can find it, selected in Live's Preferences.
More information about the LiveAPI can be found on these sites:
http://www.assembla.com/wiki/show/live-api
http://groups.google.com/group/liveapi
According to the LiveAPI documentation, the Clip object has a "name" attribute which holds the clip name. Presumably that's what you want to send in your OSC packets.
Also, it's worth mentioning that the Max/MSP support in Live8 will probably be a lot more comfortable to work with than LiveAPI, which is pretty much a dead project. Max/MSP supposedly has OSC support, which was added to support the JazzMutant Lemur, but I'm not sure how much of that made it into Live. Anyways, it's worth keeping in mind for when Live8 is released.
I know about Max 4 Live, but as I see it, it's kind of a different thing. Yes, it will probably be able to interface with Live to do all the stuff which people do now with LiveAPI. Some even think that M4L may not even go through LiveAPI, and use some internal interface instead (since Ableton and Cycling 74 are developing it together). From the promo videos on ableton.com site I think that M4L will mostly be about making and modifying sound, and not so much about controlling/reading other instruments, effects, clips etc.
I would not say that LiveAPI project is dead, because a lot of hardware MIDI controllers rely on LiveAPI to do some auto-mapping magic. When you look at the MIDI Remote Scripts folder in Live, you'll see that each controller has it's own folder with a python script. So I definitely think that LiveAPI is going to stay, and that this door into Live will remain open. They even created a new folder called Framework which contains some newer code, probably required for the new Akai controller to work with Live (that is what people believe in theory).
The application I plan to use the playing clip's name is called vvvv, so I don't want to have to bring Max into this, because it is not really needed.
I had some success with someone's modification of the original LiveAPI code, but only worked when I request all the clips' names, not when I asked for just a single one. I didn't have time to play with it later, and the thing for which I was preparing this has passed. I plan to work that out eventually, but it's not that urgent anymore.