Hardware :: Serial Communication Only Works In One Direction - Why Is So?
Sep 21, 2010
Running RHEL5.5 on a Dell R710 server. I installed a 2-port PCIe serial card, built the driver, and installed the kernel module. The ports show up in /etc/hwconf, lspci, kudzu, /proc/ioports, etc., and I now have two new device entries...
/dev/ttyE0
/dev/ttyE1
When I connect a null modem cable from port 0 of the card in the new computer to serial 0 of another computer, I can receive text from the other computer. When I do this... code...
I am in verse to understand the serial communication between guest and host.I have just added a serial port through VI Client selecting "Use serial port on host"(host being ESX host).If I am on VM and run :
ll > /dev/ttyS0
I understand that it should get displayed through ESX Host. So On ESX Host, I typed:
When I try to Sync a Palm Vx to my PC through serial port I get a communication error message in the gadget. My PalmOS Devices application is already configured to use tty0 or tty1 in unsuccessfully trials. I have a lot of information in the addresses, agenda, notes, etc. and do not want to loose that information gathered for years, nor to return to Windows.
As a test, I used a serial mouse in the serial port and It didn't work. I verified the Bios Setup and COM 1 and COM 2 are enabled.
I also checked my system serial support with the following commands:
And messages were OK when compared with typical outputs. My machine is a Pentium 4 CPU 1.6 GHz, in a U8668 motherboard (Award Software International). I have Ubuntu 10.04 LTS with Gnome.
I am new in Linux and don't know Bash yet. I had followed indications from Internet tutorials successfully, but I don't know how to proceed in this case.
Not really sure where to post this, so here goes... I installed apache2, php and MySQL via LAMP and everything seems to work fine but when I try to open the COM1 port to do serial communication via PHP, I get a permission denied error.
I've also tried using /dev/ttyS0 instead of COM1: but no luck. Anyone out there know what I'm doing wrong? I don't know if I need to set something up in apache2 or php or if the code is just wrong. I'm on an Acer Aspire One with Ubuntu's LNR 9.10.
I have been trying out serial and parallel data communication on Fedora 13 Beta. I can easily see the list of serial ports through:
Code: setserial -g /dev/ttyS[0-3] And can also write some data through: Code: ll > /dev/ttyS0 But I am unable to see parallel ports I can see something like: Code: /dev/parport0 But when I try out: ll > /dev/parport0 It throws error.
I am new to linux terminal programming and all but i want to set up a simple serial communication from my desktop through USB port. The actual idea to to write some data in the terminal and build a terminal program that sends the data to the usb port with a fixed baud rate. are there ready made terminal programs available for this simple communication?or atleast any Graphical tools which could help me build and design such a terminal in ubuntu 9.04?
I am trying to get two way serial communications going between a Windows XP system and a Linux system (RHEL 5).I have /sbin/agetty -L 9600 ttyS0
in /etc/inittab. I am using a generic USB to serial adaptor on Windows (Unitek) and a null modem cable. I have putty configured for 9600 baud, 8 bits, no parity, one stop bit, no flow control.I get the login prompt from agetty in the putty window but input does not work; I see weird characters in the putty screen. I can echo output into the device from windows and see it, but
cat < /dev/ttyS0. just prints out weird characters from what I type.
On my CentOS 5.2 install I've installed a dual-port serial card based on the NetMOS 9835 chipset. I've followed the serial instructions, but everything they tell me to do is already done - see setserial outputs below. I've compared these values to the lspci output (below, NetMos card is at the bottom of the output) for the card and it appears right. Problem being, I can't use the serial ports. Oh and I did use search, and looked at every 9835-related article before posting this :)
I am hoping to be able to get an old serial-touchscreen to work with a usb/serial adapter. I had this touchscreen working some years ago on different hardware. I would like to hook it to the machine I am setting up as a multimedia host with mythtv among other things.
Following the instructions I left behind when I got this to work way back when does not work. See [URL] ....
This info is a work around to get the xserver to see the touchscreen. [URL] ....
I do know that the touchscreen works as I am able to get garbage on the screen as in the first part of my howto. But I have not had any success getting xorg to see it. I wish I had posted a copy of the xorg.conf at the time, but......
There is an issue with the current xserver in testing that I am hoping the next update (in unstable) will fix when it gets pushed to testing. That is that Code: Select all# X -configure fails with a segfault. So I am not able to generate the xorg.conf needed to get it to work. I was going to post a bugreport, that is when I found out there is an update in unstable, so I am waiting for it to get pushed at the moment.
Anyway I am hoping that I can link /dev/ttyUSB0 to /dev/tty0 and get it to work. I would like some kind of guess as to my chances of success before I go to all the work of getting the monitor hooked to the host.
I have a bit of a dilemma. I'm attempting to use a microcontroller to send MIDI messages over a virtual serial port. I want to (eventually) read them with Mixxx. I'm using an FTDI chip, so I get a /dev/ttyUSB0. I've tried spikenzielabs' Serial-Midi program, but it doesn't see any serial ports. NOTEMIDI looks really old and won't compile on my 10.04 LTS machine.
We have a new machine with RedHat enterprise 5 on it. I need to connect a serial cable to the serial port and talk to another system (old alpha system) instead of using a VT connected to the alpha.Does RedHat come with anything like Keaterm/hyperterm/etc etc?
I can't seem to find anywhere that allows me to change the direction in which text is displayed/entered. I'm trying to change from "left to right, top to bottom" to "top to bottom, left to right".
I have laptop with Ubuntu wired to ferdora 12 server. Server RDP control to desktop is working.Laptop to server is not.See screen shots.I am thinking VNC server is not installed or configured properly on server.
I have an old Logitech Wingman analog joystick connected to a game port on a Creative sound card. At this point I've got the system to see the joystck and was able to run jscal. I was also able to run jstest. I was able to see positive & negative numbers moving the joystick in four directions. However, when I try 2 different MAME games or Open Arena there is no right direction. Pushing the joystick right only stops it from going left.. Up and down movement seems to be OK.
Can someone point me in the right direction for adding SSL to a webpage?I've installed Phpmyfaq, on an Ubuntu 9 server, but I want to set it up so that logging in is done securely.
I have been pouring over pages from some days over this one and come to my end.I have Meekat Guest, Xp host on Virtualbox; set up for folder share on virtual networking.Xp can see Linux shared folder, can withdraw to itself, yet cannot deposit to shared folder; error received "Disk write protected or in use"Linux access to 'workgroup' - xp machine is seen yet when clicked on returns the error of"Unable to mount location - failed to obtain share list from server"smb call from Host returns "Connection to STENCILCUP failed (Error NT_STATUS_UNSUCCESSFUL"
I'm currently setting up a squid proxy which will be installed on a debian system configured as a bridge eth0/eth1 as br0. The problem I'm having is that port 80 requests are being proxied both ways where I only want the requests coming in via eth1 to be proxied.
Is there a way to do this? I've already tried changing the "-i br0" in the iptables redirection to "-i eth1" but no data appears to go through it.
I tried to set up NFSv4 with idmapd between two Debian/lenny installations. On the client, the user "xyz" has the UID 501 and on the server "1000". Changing UIDs and setting up NIS is not possible, Kerberos unwanted. I tried to set up NFSv4 with idmapd and it is only working from server to clienthen I list directories on the server, belonging to the user "xyz/1000", the owner is correctly displayed on the client as user "xyz/501". But when I create a file on the server, it is created with UID 501 (should be 1000). The configuration is quite standard, idmapd.conf was generated automatically, NEED_IDMAPD is set to "yes" and starting properly.
The main exporting directory has following options in /etc/exports: rw,fsid=0,insecure,no_subtree_check,sync and the mounted directory has:
I've been using Ubuntu for about 6 months now, but haven't had a need to start scripting until just recently. I know programming basics, but that's about it.Anyway, I have a program that I would normally run in this manner (note that I didn't create a permanent alias because I've been moving the program around a lot):alias dx='python /path/to/dxProgram.py' dx A_input.dx B_input.dxSo, you see, program dx takes two input files, and 'A' must come before 'B'. I have a folder full of these types of files that I'd like to loop through with this program. They're named as follows:
im trying to learn javascript. so i choose to start out making a image slideshow banner that auto scrolls on load no special buttons. so since i had no idea were to start i found code that was free to use commercial and non commercial and ill be able to change it. heres that code:
I work with modbus protocol(MODBUS/TCP to MODBUS/RTU gateway server) and write a program for work with mbusd. when working with usb to serial adapter and cable, my program works without any problem. but when working with serial cable does not work (without usb to serial adapter) ; when mbusd is runing and i run minicom program in part initializing modem my program works and when minicom lock the serial port my program stop. when close minicom "with no rest modem" (ctrl+a and press q) modbus program and my program works without any problems.
in builder site (mbus.sourceforge.net) posted : note that currently mbusd can't operate with RS-232/RS-485 converters with direction switching by RTS pin. Use converters with automatic data direction control (i.e. Moxa Transio series).
initiated update. Grub update required user input. The 'help' message is incorrect. Attached is a .jpg of a Grub message during the upgrade. Question: how does this get corrected? I would post an alternative wording but honestly,
If the arrowhead points up, the standard behavior is to sort with lower values first and higher values later. In my ubuntu install, it does the opposite. Names and dates sort descending when the arrow points up.
why do we have to define both Source/Destination AND Direction when building firewall.Isn't direction= source->destination? what would happen if source and destination were swapped?
How do you interface with the Linux I2C driver from kernel space? For example, if I had LEDs connected to a GPIO expander on the I2C bus, how would I blink them twice before going down for reset from machine_reset()?
Essentially, I believe I need to call the functions i2c_smbus_write_byte(), i2c_smbus_read_byte(), etc. But these functions require I2C client data that I do not understand how to supply.
I am writing a code which communicates between 2 processes created by fork() statement. Parent reads a file and write the data into a shared memory and sends a signal to the child. The child then receives a signal from the parent to start reading. After finishing the read operation the child sends a signal to the parent asking it to resume its action. Some things are going wrong in my code.
1. segmentation error in memcpy() statement. 2. terminal hangs after running the code. 3. Synchronization problem between processes..
I have been able to use bash to initiate a google seache via firefox. I would like to either copy the source page to a file via wget or send firefox short cuts to the other terminal's firefox search page to put the html file in a directory. I seem to remember but maybe incorrectly that there exist hexadecimal codes for each keyboard shortcut in firefox. Maybe these could be echo-ed from bash to the firefox search page.
