Ubuntu :: Write/Read On /dev/ttyUSB0 Using C Or C++
May 31, 2011
Recently i acquired an electroencephalograph (EEG) and started to experiment with it, and i need some way to write or send a couple of Hex numbers to the EEG so it will start working, and then to save the data on text file, or at the very least see the output on the terminal using C or C++, i found some programs around the forums but none seem to work properly and more often than not, The EEG is recognized as /dev/ttyUSB0 has a baud rate of 921600.
What are the possible problem when Windows access the file from Ubuntu got Read Only even though have a full permission to read, write and execute the file? Ubuntu to Ubuntu accessing the file there is no problem only Windows got a problem.
I did install QLandkartGT and the plugin to use Garmin with it and it looks like it work, but when I do press "Live Log" I get the error message; "Device Link Error. Failed to request real time position. Realtime thread failed. Failed to configure USB: could not set config 1: Operating not permitted".
I also get a similar error when trying to download tracks; "Failed to download tracks. Failed to configure USB: could not set config 1: Operation not premitted".
My guess is that Ubuntu do not allow programs to use the USB port, so my question is how I do allow this program (or all) to use the USB ports.
I just installed Ubuntu 10.04 on my system, and I put in a really old game CD for my really old computer. I cannot run the setup program , however because "it is not executable". I can't change this , because it is read-onlybut I can't chane this either. As I'm new to this, I was wondering .
I have a netbook with Ubuntu 10.10 installed in it,and a Pc with also ubuntu 10.10 in it , but x86_64.
I want to copy some iso files and data from my user home directory on the netbook , to the user home directory of the other pc , using a 8 GB usb formated in ext3 with gparted in my pc.
One iso is a windows 7 one to burn then with K3b , as i need to have windows installed in that box. Also of another iso that i have to burn too (windows 7 recovery disk) , and 3 anti-virus trials for windows.
As the usb is owned by the root (or more properly the mounting point,no?), and i can't use my user to copy data to it i usually do :
Usually , what i use is "sudo nautilus" then go to the place where is the data , copy it , and paste it then in the usb. Then in the other pc i do a chgrp and chown to the iso or file.
But , perhaps this is not the better approach. I have investigated a bit , and i think that i have found a better way , but i have some dudes.
The method is change the owner,group and permissions of the mounting point:
Code: cd /media ls umount /dev/sdb1 sudo mkdir usb
If i do this steps in both computers, with each user,in the netbook i can copy the iso to the usb (as fox can write to the mount point of the usb ), but can the other user in the pc 'mulder' read the iso , so be copied to /home/mulder, and then be able to burn it in k3b with success ?
I suppose that having 766 , it should be able to read it , but would have the own of the file ?
How important is not to only be able to read it , but also own it ?
I suppose if the user ID is the same , wouldn't be any problem ,as each ubuntu would supose that the file is owned by their user.
Perhaps the user name change,but if the ID is the same , the user is the same for ubuntu , not any different, no ?
sudden of all all USB drives and sticks I put into a PC will not mount with read/write permissions (they did before). I can still copy to them, but only when I am root. I am on Maverick I've noticed though that if I run disk utility, then UNMOUNT the partition, Check File System, Mount the partition back, I get read/write access..
I would like to be able to read and write on hd formatted as Hfs+ not journaled...I know it is possible, but still I can't since ubuntu mount them with a different user: 99.If I add my user to the group 99 will be fine? or exist another way to write on such file system?if use hfs+ not journaled it will be less safe for the files?
Recently my Ubuntu system decided to crash. Sometimes the mouse freezes, sometimes I just can't open anything, and other times I can access the terminal but can't write. I can open files as read only both in my /home partition and in /var/log, but I can't write at all. Sometimes I get Bash: input/output error. I *can* "ls /proc", if that makes any difference.
I find that if I reboot, the problem goes away for a few minutes and then reoccurs. I can read/write to my other (windows) drive, although when I did a chkdsk in win7, I get a "An index entry from index $0 of file 25 is incorrect" message. Is the disk failing? Just a few bad sectors? Maybe the filesystem is corrupt? Why can I read but not write?
I want to make a new partition that I can read and write to from Ubuntu 11.04 and Windows 7. I haven't used Ubuntu much since 8.10 and it seems that I remember it being much easier to do then. I'm using this partition to store my music, pictures and videos on if that is of any relevance. I also need this to be something that can't mess up my windows side of my computer as I need that for work.
I am running Karmic x64 on a HP laptop that has a cd/dvd burner. I have a r/w cd with files on it and I wish to add/remove files to it. After it mounts automatically on insertion, I unmount it and remount with: sudo mount /dev/sr0 -t iso9660 -w /media/cdrom (I tried assorted other hare-brained things also) but it always says that the filesystem is read only. Do I need to use a different device than sr0? Is it even possible under Ubuntu?
I recently installed Ubuntu 10.04 using Wubi on an ACER Aspire 5000 XP laptop. Everything runs ok and I can access my Windows folders from Ubuntu through the host directory but only as Read Only. I have checked to make sure that the Windows folder I want to access (My Documents) is not designated as Read Only in Windows.
We have a network with several computer. We have two file servers (don't ask why) an Ubuntu and an XP as well as many clients. Setting shares on Ubuntu was easy and all clients can see them read and write. but I can't get the Ubuntu clients to see the SMB shares on the XP properly. This is my fstab:
I have shared two external harddrives via samba on ubuntu, but only I can access it. The reason being is because I have logged into linux, and become the owner of the external hdd's. On the permission properties, I can see that the group I have created every other user under has "No Folder Access", and if I change this it reverts back instantly. So frustrating, I've tried to chmod it which hasn't done a thing. The owner of the external hdd's seems to be the only person who can access it over samba.Is there anyway I can get normal users to just read and write to external hdd's?
Just wondering if there is a way to show the stats of the hard drive(s) in the computer mainly the current read and write transfer rates. Similar to the network graphs that show the Download and Upload speeds, but concerning the hard drive(s) in the computer. I know you can monitor the hard drive temperature, but I haven't seen anybody monitor the stats for the hard drive.
I don't want to have to download the kernel source and uncomment out CONFIG_UFS_FS_WRITE=yes and build a custom kernel ever time I update the kernel. Is there a better way? Like when Ubuntu.deb repositories claim a stable kernel is there an auto config script when installing from synaptic -or- aptitude? Like any way to add this one config opt to .deb kernel W/O building custom one from source?
I am not the best with Linux but at the same time like to think I am not the worst, Anyways like stated above my dvd drive is saying its read only and i would like to make it read/write here is some info:
*-disk description: ATA Disk product: ST3500418AS vendor: Seagate physical id: 0.0.0 bus info: scsi@0:0.0.0 logical name: /dev/sda version: CC46 serial: 9VMRTLT1 size: 465GiB (500GB) Capabilities: partitioned partitioned:dos Configuration: ansiversion=5 signature=0005ce96
I need to read and write to a serial device. When I connect via gtkterm, I need to toggle DTR before I can communicate with the device . My problem is that I cannot emulate this in C++.
I want to write some code that can setup a comport, toggle the DTR, then read and write strings to the port. However all my attempts have been fruitless. My serial settings are B9600, No parity, no hardware control, 8 bt characters and 1 stop bit:
I started a thread in the hardware section, but I've narrowed it down to being a software issue. The problem is that all USB devices are written to at about 1MB/s, and is read at equally slow speeds. After testing my computer on an older Ubuntu release (8.04 32bit), I verified it wasn't a hardware issue, because the read and write speeds were like they were supposed to be. Then, I downloaded the 32bit release of the Ubuntu version I'm currently using (an up-to-date version of Natty) and booted the live cd of it. It was equally slow there as well.
The read/write speeds are equally poor on openSUSE and Arch Linux, so I don't think that it's an issue with Ubuntu, as much as it seems like a kernel issue (or maybe not, you guys can correct me if it seems like it isn't ).
I've extracted a few files through the archive manager through Ark (as well as through the command line) and some folders/files that were originally in Japanese are not properly displayed in the terminal or file browser. I can't delete them nor open them; I am informed that this file does not exist.I am running Kubuntu 11.04. I had a similar problem in Ubuntu 10.04 in that the text was not displayed properly, but the files were readable and writable.
On opening nautilus,it shows the XP ad Fedora partitions.Clicking on them mounts the partition.However,XP partitions are mounted in Read/write mode,whereas Fedora partition is mounted only in Read mode.What changes should i need to make in /etc/fstab to enable Read/Write access to Fedora partition as well?
I can't see any option for recursive directories in nfs in fedora 13.
This is my set-up:
save and exit.
When i mount the directory /media/Data from another Fedora 13 box i don't have read and write permissions for each and every file. The -R recursive option would be handy unfortunately this option is unavailable. The red hat docs have not been helpful in this respect.
The mounted partition is of the ext3 type. With the nfs-3g type i don't have any issue however most of my directories/partitions are of the ext3 type so i need get it sorted.
I changed my user name id number to the same number on all boxes thus giving me write access. There must be a better solution than this.
I installed SAMBA and SWAT, latest versions. What I want to accomplish is to give Windows users unlimited read/write access to the entire filesystem, eg. (/). Barring that, I'd like to at least be able to configure full access to individual directories.And by "unlimited", I mean being able to edit and delete everything that would be normally accessible only by the root user. I want to grant the Windows users of the shares access as if they were root users.