General :: Use A Rs232 Device That Uses The Usb Port?
May 18, 2010
been trying to use a rs232 device that uses the usb port. it calls for a virtual com port to be created. i am running on ubuntu 10 and get hella confused with the search results i have come across.some call for the usbdevfs which apparently doesn't exist under lucid. another had me do use some "magic" in getting it to work.they provided a script mountusbfs.sh
Code:
#
# Magic to make /proc/bus/usb work
#
mkdir -p /dev/bus/usb/.usbfs
[code]....
of course when i tried it the domount command doesn't exist so i modified the above script replacing the domount with mount and it seemed to do something things. usbview is specified as the determining factor whether or not you have the usbfs mounted properly. it wants to use proc bus and ubuntu doesn't use that anymore apparenlty. i have read that i need to enable a usbmon (flag?option?) in the kernel to be set. which it isn't when i followed the steps to check.
I am trying to interface a machine (lock in amplifier) with Ubuntu using a RS 232(25pin) to USB cable. I wrote a program in c to interact with the machine. I think the machine is detected (after connecting the machine a file is created in folder /dev with name ttyusb1. I heard that ubuntu has all the header files required to interface with the port. with the help of a person i wrote this program (please see the attachment below.) but i don't know whether the commands are right or wrong. the program is compiled. but when i run the program it is getting stuck. i have to stop the program using Ctrl+z. if anyone knows these commands (how to write to or read from the port) please help me with this program.
I want to send something through the serial port, for example
[code]...
the point here is send some numbers to a couple of 7 seg displays, so I will wire a RS232 chip on a protoboard, the logic after the RS232 is not an issue, but how can I assure the data is being sent right from my linux box to the RS232 chip, the one on the protoboard? Do I have to write a C program to read the strings and then send them to the serial port?For example if I wanted to send this to the displays:
[code]...
So I guess the simplest way is (Supposing I can deal with the stream so it is filtered and only display the number array) $ ifstat > /dev/ttyS0 But, how do I know if the RS232 will take them as the right characters?
I was able to write a script on Linux Shell for send and read data to a serial port. But I�m facing a problem now. If by any mean I send to de device anything else than the predefined strings, stated by the manufacturer, the device ceases to respond. The only way I found its to turn off and then turn on the thing again. Which its very impractical. Its there any way to "reset de UART chip on the device" or send some string based on the RS232 standard that clean the device buffer?
I installed ZTE MF 626 modem in my F10 with kernel 2.6.27.12-170, i run usb_modeswitch and so far things happened normally. Watching through /var/log/messages it says that F10 detects two port device for this modem: ttyUSB1 and ttyUSB2, and in the sequence it disable port ttyUSB1 BUT Network Manager still set this port.I mean, when i connect via wvdial appointing to ttyUSB2 i get connection, but Network Manager fails to do it appointing to ttyUSB1. How to change device port in Network Manager?
I have been working on writing a small rs232 driver like minicom for months. I am almost there, I have the interrupt service routine running, I can read() ok. However when I write(), it returns the number of characters written, 1, but nothing is actually written out the port. I researched termios, and they say that serial port programming is really messy in linux/unix.
I am probably not setting up the port parameters correctly, or my write() function is not doing what it is supposed to. As I said, write() is returning successful. Other comm programs run ok (picocom & gtkterm) on my hardware. I am running knoppix/debian on an ancient computer. I saw other guys using slackware.
Startup script. I have a problem with an error on system boot: hub 2-0:1.0:unable to enumerate usb device on port 5
This error is continuous, filling up my system logs. It is also a known kernel bug. I found a solution here: [URL] but it is only good after I boot. I have tried to make a startup script in /etc/init.d in the following manner.
sudo mkdir /opt/usb/ sudo gedit /opt/usb/usbproblem.sh #!/bin/bash # chkconfig: 345 91 19 # description: stop usb problem on startup case $1 in *)
echo "fixing usb problem" cd /sys/bus/pci/drivers/ehci_hcd sh -c 'find ./ -name "2-0:1.0" -print| sed "s/.///">unbind' cd ~
esac exit 0 #End of boot script ##
sudo cp /opt/usb/usbproblem.sh /etc/init.d cd /etc/init.d sudo chmod +x usbproblem.sh sudo update-rc.d usbproblem.sh defaults 92 20 but it does not work.
how to access serialport(RS232) data using OpenGL.Heard about SDL(Simple DirectMedia Layer),but didn't get how to use SDL and OpenGL to access RS232 data.
Jun 19 20:34:08 localhost kernel: [352155.875643] hub 2-1:1.0: unable to enumerate USB device on port 2 Jun 19 20:34:08 localhost kernel: [352155.851515] usb 2-1.2: new low speed USB device using ehci_hcd and address 17 Jun 19 20:34:08 localhost kernel: [352155.677964] usb 2-1.2: device descriptor read/64, error -32 Jun 19 20:34:08 localhost kernel: [352155.503404] usb 2-1.2: device descriptor read/64, error -32
[code]....
The Motherboard is a Intel Desktop Board DH55TC, Sockel 1156, mATX, HDMI
After installation I boot a few times and used F15 on my Dell Inspiron 1564. But now I can't boot anymore. The screen just shows "unable to enumerate USB device on Port 4" and just hangs there with a blinking cursor below that line. I have no USB devices attached though.
I am trying to use the printer port. But, I get this
Code: Broadcom EJTAG Debrick Utility v1.6r-hugebird Failed to lock /dev/parport0: No such device or address johnh@tux:~/Ubuntu One/hh$ run from johnh I permission denied sudo-ing I get above.
I'm running Slackware 13.37 64 bit. I run it on an HP2945SE AMD Turion x2. I am getting an error during boot up unable to enumerate USB device on port 5. It filters throughout the rest of the boot up commands / results. It doesn't seem to matter if things are plugged up to the USB ports or not. Also it doesn't seem to affect anything on the computer. Its just irritating.
[ 130.876406] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 130.876453] usb 3-2: USB disconnect, address 6 [ 131.200399] hub 1-0:1.0: unable to enumerate USB device on port 4 [ 131.396382] hub 1-0:1.0: unable to enumerate USB device on port 4
[code]....
That is what I have exactly pluged, the webcam on the top of my screen and an external mouse. Btw, I can plug USB devices with no problem, so I am skiping this error since long time ago, but I don't understand this message and I would love to do it.
I have a host and a client both running linux. Host has internet through eth2. Client needs to share that connection. The computers are connected directly using a crossover. I can ping from both fine. I figured I needed to port forward eth2 to eth0 to gain internet access in the client. How?
Code:
eth0 Link encap:Ethernet HWaddr 00:26:18:a6:fd:a3 inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::226:18ff:fea6:fda3/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
I am building a custom RedHat+<our-software> installer iso for our own appliance. I am using Red Hat 5.4. The appliances has two on-board eth interfaces. On the back panel of the appliance, these ports are marked 1 and 2. When I install RH, I find the device names assigned such as eth0/eth1 are arbitrary. I understand this is to be expected with kernels 2.6+. Most of our customers connect their eth cables to the port marked 1 on the back and assume they should configure eth0 to make the device reachable. However, sometimes port 1 gets assigned "eth1". This is not a blocking issue, but its going to confuse our customers and we wanted to make it easier on them.
From reading online discussion boards, I know HOW to switch the assignment of the eth names. However, what I am do not know is whether I need to switch them at all. So I have two questions 1) Is there anyway for me to tell which eth mac corresponds to which port on the back? Since they are soldered on the motherboard and not movable, I would think there would be some way to figure out that x mac address corresponds to the upper port (marked '1' etc). 2) Is there a way to tell this by running a linux command? We need to do this automatically so I need to be able to figure it out at install time from the kickstart post-install or similar.
If I forward port 5764 to port 80 to my VOIP device, I can nmap and get a proper connection. If I forward port 5764 to port 22 to my server, it comes up filtered. It even happens if I try forwarding port 80 to my server. So I'm sure it has something to do with my server, but I'm not sure.Here's my Linksys iptables:
Recently my Ubuntu 10.04 was booting slow and to figure out what was going wrong, I booted Ubuntu in text mode. There I found it was hanging on for 5-6 sec showing "unable to enumerate usb device to Port 1". I know it has something to do with Port1 / usb device, but could not understand and solve it.
My computer won,t boot up anymore, i keep getting the following mistake message: Unable to enumarate usb device on port 2. Don,t know how to skip that, and continue to desktop.
The code compiles without errors, but doesn't catch any input text from the device attached to RS232. I have tried it with Rx and Tx connected, but didn't receive my text back. It works OK if I substitute /dev/ttyS0 with an ordinary file, but any attempt to use /dev/ttyS0 seems to lead to an empty answer string. I tried this on a PC under Ubuntu Linux 7.10.
I've started development on a ARM board. The ARM board displays it's command prompt through it's rs232 output. So I open putty/minicom (rs232 display) and can see and interact with the ARM linux system through my PC. The ARM root fs is on a USB pen, So I cross compile on my PC, then plug the pen into my PC copy the exe into the home/usr etc folder. Then unplug. plug it into the ARM boot the ARM and from my PC rs232 window can run the code. However plugging/unplugging is taking an age, I'm sure there must be a way to transfer the exe across the rs232. I've tried to use putty minicom to do so throught various methods xmodem etc but don't seem to be able to. I think I must have to do something on the ARM end but am unsure what?
I have (at least 4) native USB ports that contain flash drives. I know that the /dev/sd[abcd] devices are created in the order they were inserted, but say you have all four plugged in at boot time, or further, they can be plugged and unplugged in real time. At times, /dev/sdf, /dev/sdg, etc. are created as well. I'm ignoring external hubs for now.
I need to know which drive is plugged into the "top port on the front panel", etc, by physical location. From dmesg I can check right after booting and get the physical assignment of a PCI device, say, PCI 0000:00:10.3, as being assigned to the EHCI usb bus. From /proc/bus/usb/devices, and the "T:" field, I have learned that the physical connectors I'm interested are known as USB Bus 1, Port=00, Port=01, Port=04, and Port=05.
From lsusb I can see all sorts of information from the USB point of view, but with no /dev/sd references.
From /proc/scsi/scsi, I can see what scsi devices have been created, with a count consistent with the number of flash drives plugged in, but no USB data.
So, I can get lots of information from the USB storage point of view, and lots of information from the SCSI point of view, but nowhere can I find how to correlate them. In other words, if I want to mount the drive plugged into a given physical slot, how can I find the /dev/sd device I need to mount? udev isn't really interesting here, because I'm just looking for the information that udev would use to answer the same question.
I've done some heaving exploring in the /sys and /proc filesystems and have not yet found where the USB and SCSI worlds intersect.
The closest I have found is (where "Port" is the physical port number from above):
This seems to have some mapping to the physical port and references a "/dev/sd[a-z]" value, but I don't know how reliable it might be, nor do I know if my having to increment that physical port by 1 is meaningful. Anyone have a simpler approach?
So, my goal becomes mount /dev/<sd that was created for the top slot> /mnt/top mount /dev/<sd that was created for the bottom slot> /mnt/bottom etc.
a few day ago i have checked my application and make rs232 cable converter to communicated it. And not detected, why? FYI, this is my lsusb command, but in my dmesg, was not found. check this out, (usualy there is another rows, just like ".....converted to ttyUSB0....")
I am writing a program to send data over serial port but the sending and reading operation is not occurring as desired to be... Below you can see the read and write parts. Could you please help me to find where I am doing wrong...
When I compile and run the above programs Reading part does not read the 13 bytes once it first reads 8 byte then 8 again then 2 and so on. It always divides the sent data...
VERY new to linux, erm but I have an issue that needs solving!I recently moved to university, where their network blocks sftp port 22, this means that I cannot connect to my FTP server which is running a version of linux.Now I've got this ftp server connected to a seedbox and it was created using the following walk through..Code:I have written this guide for a friend, but I though it would be useful for others as well.
There are several guides floating around, but I found that most always cock up in some way. This one is tried and tested to work on Debian Etch (on an OVH rps, but should apply to most servers).If there is a new stable release of rtorrent/libtorrent then I will update this guide to show you how to update it (without reinstalling the whole server).
At the bottom there are also instructions to install ftp access & some network monitoring software.Basically, I would really like someone to be able to construct the commands on how to change the listen port for sftp connection on linux or add another port to the list that Linux would use so that I could put in through putty.
