First of all a statement: I'm a newbie when it comes to programming for the Mac. However I have an assignment which requires USB communication with a device so I thought I'll start with something basic.
I took the code from here, built it and ran it from the Terminal. It starts up and writes:
Looking for devices matching vendor ID=1351 and product ID=8193.
Starting run loop.
However after this, if I plug in and out USB devices (I tried: iPod, GPS, mouse) nothing gets written on the screen, although as much as I understand there should be whenever I connect and disconnect a device.
What am I doing wrong?
Thanks in advance.
You can also use system_profiler SPUSBDataType on a terminal
I found /Developer/Applications/Utilities/USB Prober to be of great use.
Related
I'm trying to use example code provided by X-CUBE-IAP-USART package to develop IAP FW for STM32L0xx device. I'm using STM32L073 Nucleo64 board for development.
When I send compiled FW using TeraTerm's YMODEM protocol nothing happens.
Only thing that is being send to target STM device is: "ota_test.elf166988 13332031541 100644¶Ê" over and over again. When I debugged example code I was getting HAL_TIMEOUT on receive. (rework example code to work with interrupts?). I've triple checked my USART settings so that is not the problem. Cam anyone please help me or send some functioning example code please? Original example code was written for STM32L073 eval board, but I've ported it to work with NUCLEO board, maybe I've made mistake there but, I've configured all peripherals exactly as they were configured in example code.
I appreciate any kind of help.
Thank you.
I am using STM32L476 and faced same issues while writing boodloader for my project.
The problems I encountered are:
HAL_UART_Receive() not working properly, always returning HAL_TIMEOUT
After the uart problem was solved, I was still not be able to upload bin files. Where I noticed that the codes were trying to delete the wrong memory address.
Applied solutions:
I changed the usart conection options. I used DMA channel to receive ymodem packages.
In the FLASH_If_Erase() function, pEraseInit.Banks configured 'FLASH_BANK_1' instead of 'FLASH_BANK_2'. I guess this was a bug and needs to be updated by ST developers.
I added the bootloader projects link where you can find all codes and the changes. Hope it helps with your problems.
Link : https://github.com/yelkovany/Embedded_codes.git
I would like to make a Graphical interface for a home-made program using SFML on Raspberry Pi2. I am using Raspbian. I recompiled the graphical lib
It works fine unsing startx first, then using my application, which wors perfectly fine.
But I can't figure if it is possible or how to launch my application directly after boot without launching startx (just to optimise the cpu of the Raspberry).
Starting my program direcly after boot, I get the following error:
Failed to open X11 display: make sure the DISPLAY environnement variable is set correctly.
Aborted.
I already tested the classic export DISPLAY=:0.0 but without sucess.
I interested myself in x and xinit, but I am not sure that would even do it.
Where should I start looking? I don't need a complete solution, even a hint or an idea would be nice!
I checked to see if it was possible to open a graphical app without the X desktop environment and as that answer states, with Firefox at least, you need the X server which SFML also probably needs in order to create a window.
The answer states:
Basically something like:
$ X
Then you just start Firefox in this X server:
$ DISPLAY=:0 firefox
You can switch from the X server and the framebuffer by using
CTRL+ALT+F1 and CTRL+ALT+F7.
You could try that and see if it helps.
Also, still searching, I found a forum post on the sfml website about what you're trying to accomplish stating somewhere:
SFML requires OpenGL, so as far as I know you need at least X running,
but you probably don't need gnome, KDE or a similar Desktop
Environment on top.
The forum guy asking for help seems to have managed to get X11 and a SFML basic render window to work on Ubuntu server after someone posted a link to xinitrc. I guess, that's the route to go from here.
I can find nothing on how to do this. I am programming an Intel Edison in C and an Android phone in Java. I want to pair the Edison from the Android phone. I would think simple pairing (sspmode 1) would work but I get an error message on the phone about a wrong pin where no pin was requested. With sspmode 0 I get asked for a password but have no idea what it is as it is randomly generated in my NoInputNoOutput Edison. We have everything else working. If we pair from Edison manually, the rest of the code can connect and send bluetooth messages back and forth from the Edison to the phone. But pairing from Edison to any random phone that walks by is not acceptable. I think it is called Bluejacking.
I have seen some posts about using simple-agent but frankly what I understand is that BlueZ security changed so much between 4 and 5 that most all that I see doesn't work. I also see that the switch from 4 to 5 broke a lot of systems so I don't feel alone. I would try it but simple-agent is not on Edison and I have not found a procedure to install it. And as I don't know if the little I can find applies to version 5 as it all references version 4 I am feeling a little lost.
Can anyone point me in the right direction to something that will work on BlueZ 5? I am on 5.18.
The solution presented on the last post of this article does work
http://www.linuxquestions.org/questions/linux-wireless-networking-41/setting-up-bluez-with-a-passkey-pin-to-be-used-as-headset-for-iphone-816003/
Edit simple-agent, put it somewhere, make it executable, put the missing files in the same directory and run it. It must stay running for it to be active.
In my case, the missing file was bluezutils.py.
Run hciconfig hci0 sspmode 0 first
Pl use Bluz5.30.
Initially it was really difficult to bring up bluetooth using Bluez 5. It seems it was okay with Bluez 4.I have tried different versions of Bluez 5 on my LFS build. Even up to Bluez 5.28 it was not satisfactory. Now it is Bluz5.30, with this, LFS doc and lot of trail, I could manage. I feel Bluez is one of the most badly documented user unfriendly software. I also feel it is very buggy. It can hang machines forcing to hard boot the system. I have seen bluetooth forcing the Android phone also to reboot. So it is important to get the latest version of the software. But to make the bluetooth speaker work Pulseaudio was needed. It is better to get the latest version; here also LFS doc was fine.
So the process of connecting speaker was using bluetoothctl is as follows;
>> power on
>> scan on
>> pairable on
>> pair <device>
>> agent on
>> default-agent
Now the actual sound. Here pactl and pacmd are useful.
paplay -d can test the devices.
using pacmd with command 'list-sinks' can show the devices.
pacmd ->list-modules can show the modules loaded.
How to change automatically the audio output to bluetooth speaker when it is connected?
For me in one machine it was working fine, with an identical LFS in another machine it was not working. Finally it was identified as a
missing module module-device-manager with arg do_routing=1.
Once it was loaded everything was fine. This particular module was not shown in the pulse configurations. So I have to find that and load,
pacmd
load-module module-device-manager do_routing=1
One can add a line in the default configuration file available in /etc/pulse.or one can add it in the user configuration file also.Now to make the new bluetooth speaker being used to play sound. For that issue the command 'move-sink-input ' using pacmd. You can find the sink names my issuing the command 'list-sinks'.
If your speaker is not connecting, it may be that it is already connected elsewhere. If it is not so, remove-device; scan on; pair; and connect using bluetoothctl. I was worrying how to make file transfer using bluetooth (Bluez5). Actually very little information is available in LFS documention or in general in the NET. This very true and unfortunate about Bluez in general. They do not provide any real user doc or nothing is available in net. So the steps are as follows:
You need to install OBEX library. Then you build Bluez5 (if it not done already). It will install obexd. After installation you can find obexd in $PREFIX/libexec/bluetooth/obexd.This is where you find bluetoothd also. One generally makes a link for bluetoothd in /usr/sbin. A similar link can be made for obexd also. Once you start bluetoothd and obexd you can find object transfer profiles in bluetoothctl->show.If you need a phone to push objects to the computer, you need to run obexd with options '-a' and '-r '. if '-a' is not given phone will fail to send the file. Now how to push a file from Computer to Phone. For this you need obexctl, I do not think it is a finished tool, and it will not be installed while we build Bluez 5. I have seen it in the source tree and copied to /usr/bin/. It should be used to connect the Phone and when the connection is established one can 'send ' and you have to accept the request in the phone.
Starting obexd as a deamon was a problem. When obexd was tried on a text terminal (init 3) it was not possible to start since it needs a dbus session which in turn needs X display. It means one need to login an X seession before you start obexd. If you dissable X while building DBUS (--without-x) then Window Managers will not work. But there is solution with 'dus-run-session < command> [args]'. That means you can start a service obexd (like bluetoothd) in the system start-up. So just by switching on the Computer ( if pairing, trusting etc... was done earlier) one can push files from Phone to computer.
>> connect <device>
Second time onwards just connection is fine. Probably you can trust the device.
>> trust <device>
I asked this question in the Raspberry PI section, so please forgive me for posting this here again. Its just there doesn't seem to be as active as this section of the forum. So, onto my question...
I have an idea and I'm working on it right now. I just wanted to see what the community's thought was on using a screensaver as digital signage. Every tutorial I've read shows someone using chromium in kiosk mode, and while that's fine and works well for some uses, it doesn't work for what I need. I have successfully completed a chromium kiosk, and it was cool. But the signage that I need to create now, has to work without internet. I've thought about installing LAMP locally on the PI, and still using chromium. I still may have to if this idea doesn't pan out. All I need from the signage is a Title Message in the top center, and a message body underneath it, with roughly 300-400 character limit. My idea is to write a screensaver module, in C, that will work with a screensaver such as xscreensaver. The module would need to be able to load messages from a directory on the pi. Then for my clients to update their signage text, I would write a simple client that sent commands as well as the text via SSH to the pi. I want to know what other people think about this. Is it a good idea? Bad idea? Should I "waste" my time doing something like this?
Thanks in advance.
I am already using a rPi as digital signage, just over a year. I am using two different setups:
version 1 uses Raspian loading xdesktop and qiv image viewer to cycle images stored on the Pi itself, synchronized with a remote server. The problem I found was power and SD stability, when the power fails, which it will do no matter what, just when... The Sd card can become corrupt due to all the writing that Raspian does all the time. Certainly does not really need to write to SD.
version 2 uses a RO-filesystem and a command line image tool. Uses the same process to show images from local, and sync with server. But power fail causes no ill effects.
I am not using screensaver to display images, that seemed redundant to me, and unnecessary to wait for the SS to start just to display the images.
Some of the images are created using imagemagik, which is nicely dynamic where needed.
I'm writing a program in C and want it to have an option that will keep a mac laptop awake even if the lid is closed so processes can continue. There seems to be very little information available on this topic so I really don't know where to begin. If anyone knows how to accomplish this or where I can find more information I would really appreciate (i.e. will I need to work with the BIOS for this or are there built in functions?). Also, if it's easier to do it in another language that is fine as I'm not stubbornly set on using C.
You need to write a kernel extension for this. The OS doesn't support it by default because the laptops aren't designed to properly cool themselves with the lid closed and internal display enabled. SleepLess is a $10 utility that'll do what you want, too. If you warp the display or something, it's your own fault. :-).
If you want to write something yourself, LidSleep.kext looks like a good start (it does the opposite, i.e. sleeping on lid close) and comes with source code.
(It is possible and supported to wake up some Mac laptops with the screen closed by using an external input device.)
You can do this using the I/O Kit framework, see QA1340 listing 2 for sample code using IOPMAssertionCreateWithName to temporarily prevent sleep.
The link to LidSleep.kext listed above is not working, so I can inform that the author of NoSleep has made the source code available here, so you can see for yourself how it can be done:
https://code.google.com/p/macosx-nosleep-extension/
If your laptop is a reasonably recent model, you don't need to add anything. If you are running Lion, it simply works. If you're running an older OS you have to wake up the laptop by sending it a keystroke or mouse click from an external keyboard or mouse. See http://support.apple.com/kb/ht3131