I am using an imx27 and have a timer set up for 100 ms and a loop to count the pulses while the timer has not expired. I get about 90 % reliable results but every once in a while i get one that is out to lunch. I am reading in a signal that is about 500khz and counting on an transition. I usually get around 85k count. But i will randomly get a 50k count.
View 3 RepliesI'm trying to set up my Thunderbird 3.1.8 (running on Ubuntu 10.04 LTS) to play a .wav file of my choice when new mail arrives. The file I've chosen is 8,8 KB in size and lasts 3 seconds. I've selected the "Play a sound" + "Use the following sound file" options in my Preferences, but only the first second (if that) of the sound gets played - both when I click the "Play" button in the Preferences menu to test it, as well as when receiving mail. Restarting the program with my new settings doesn't help.
Actual question(s):
- Is there a limit on the size/duration of the sound one can use for such a signal in this program?
- Is there any way to modify this limit?
I need to control matrix 5x4 keypad, on a processor
i am doing by making one row low at a time, and keeping all other rows high,
by scaning coloums, the corresponding key value becomes low.
my problems is that it is taking much time to respond, like to make gpio
low to high and high to low...
This is an odd one, and it's probably just my system - I don't receive half of the new MSN messages I get sent. If I talk to someone and leave the window open, I'll get all of their messages; if I close the window, there's only a 10% chance I'll get their reply.
This happened once before, and telepathy-logger was having a fit; it's not this time. Has anyone else encountered any issues in the new release?
Amendment: Pidgin seems to work ok, but I miss the empathy integration; the pidgin plugin for notifications takes the edge off for now.
I want that I click with the mouse on the video, it paused.I notice that there is "BaconVideoWidget" which I guess is the video rendering widget but it don't have signal named "clicked":
Code:
vd = totem_object.get_video_widget()
vd.connect("clicked", vd.hide)
[code]....
I plan to make a script for the console server via mail, but I find difficulties in the reading of email applications, to email me using the mail command, but how to read the incoming mail
View 1 Replies View RelatedOn my board there is no i2c lines out. So I am trying to get i2c over GPIO by GPIO bit-banging. How to use i2c-gpio driver? Where to set the gpio pin numbers for SCL and SDA?
View 1 Replies View RelatedI'm doing the shell history audit logging using syslog to gather the command history. I'm using this well publicized method using trap and logger:
declare -r REAL_LOGNAME=`/usr/bin/who am i | cut -d" " -f1`
function log2syslog {
declare command
command=`fc -ln -0`
logger -p local1.notice -t bash -i ": $REAL_LOGNAME as $LOGNAME :$command"
}
trap log2syslog DEBUG TERM
The problem is that the trap on DEBUG will catch the next to last command executed (by virtue of the "fc" command) which is not the current command executed. TERM will catch that "next to last" command on exit, thus completing the logging of each command executed during that session.
However, CTL+D doesn't seem to emit a SIGTERM signal. What signal is actually being emitted and can it be trapped? I guess another question would be whether there is a way to trap history after command line execution? Moving to Bash 4.1 isn't possible in our "supported" multi-platform environment
I have created a pthread, and installed a signal handler inside that, same way as we do in main( ) function. The thread's signal handler is a separate function. Surprisingly, it is not working, that is the thread's signal handler is not able to catch signals. Here is the code:
Code: #include <unistd.h>
#include <sys/types.h>
#include <stdio.h>
#include <signal.h>
typedef struct data
[Code]...
I have a Socket library, written in C++, in which the method used to send data never has the opportunity to handle an errno of SIGPIPE. Thus I thought perhaps I should setup a signal handler to receive the signal, but this too is not being called.Is there something that I am missing or doing that is completely wrong? Below is the relevant code. Note that a SIGPIPE signal is generated when the Server is unable to send data to the Client (e.g. the client has terminated).Server code:
Code:
#include <TCPServerSocket.hpp>
#include <string>
[code]...
I want to interface GPIO driven matrix keypad(4X4) to my linux box.
I saw a driver source file
linux-2.6.32.2/drivers/input/keyboard/matrix_keypad.c
How can I use this to achieve what I want?
Is it possible to connect a signal handler to a variable?So when the variable changes the signal handler is called.I have a vector containing strings which i want to parse when there are one or more available strings in the vector
View 3 Replies View RelatedI have a signal handler in my tool, which is registered and used between some particular interval (i am using timer). Now this signal handler should NOT allow any other handler to be registered or invoked after this handler is once registered. Is there any way to accomplish this?
[code]...
I am writing a bash script where I need standard Input should be saved in a file and should be terminated by passing CTRL+D signal. Any clue how can I do that in bash script.
e.g.
Enter one line at a time
Press CTRL+D to finish
But unable to catch the SIGTERM signal if I do shutdown, as man pages says shutdown genrates the SIGTERM and SIGKILL signals, but we cant handle the SIGKILL signal. My code is working fine if I genrate the SIGTERM signal by Kill command, and also for SIGINT signgal genrated from the CTRL+c key.
Here is my code:
/* Example of using sigaction() to setup a signal handler with 3 arguments
* including siginfo_t.
*/
#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
[Code]...
I was trying to program using fork(). The objective of this code is to
1. I am activating a process A - SubSuctionMotors.
2. Process A is going to stop with either of this condition
a) Switch is activated - swret=1
b) Time allowed has expired
3. Stop the process A.
[Code]...
1. We purposely force the switch to be inactive to test the child process (timer), whether after 2 seconds the motor stop. It turns out to be successful in first few attempts. After some while, the program hang, nothing is executed anymore and the program is not exit or terminated. What can cause the program to hang?
2. We tried to stop motor by switch activation (if the switch is to be successfully activated, the time it takes will always be shorter than the timer allowed time). However, the program did not seems like noticing the switch has been activated, and it just stop the motor according to timer. Why it behave this way?
#!/bin/sh
trap "echo Haha" SIGUSER1
echo "asit"
count=1
while [ $count -le 10 ]
do
echo "Loop #$count"
sleep 10
count=$[ $count + 1 ]
done
echo "This is the end"
Why this is showing following error?
trap: 3: SIGUSER1: bad trap
I'm just beginning to program with GTK+, and I'm facing this issue: I want to inhibit a signal emission inside one and only one function. I've down cut my code into the smallest example I can to show you what I want to do:The "Emitter" contains a "GtkSpinBox" and it relays the "value-changed" signal, it's header:
Code:
#ifndef EMITTER_H
#define EMITTER_H
[code]....
Basically I'm intending to write serial RX signal handler.Application receives defined packages of data over serial which contains header and payload. Handler should analyse incoming stream and upon detection of header (header is 6B in length) switches to receive payload of length defined in header, then after receiving full message packs it and sends to application for handling.Problem I'm facing is that at random moments in signal I receive errors that "Resource temporarily unavailable" while reading from ttyOx device and I see that sometimes I miss incoming data.Also is it possible that if while I'm handling signal one more signal arrives and it is started to be handled parallel? If it is, what are the ways to prevent it? So I would be sure that no more signals will fire on same peripheral until I will finish handling what I have on my hands now.
Serial open and init:
Code: Select allint open_port(int port_nr) {
int fd; /* File descriptor for the port */
switch (port_nr) {
case 1:
fd = open("/dev/ttyO1", O_RDWR | O_NOCTTY | O_NDELAY);
break;
[code]....
I'm learning Signals, and I have a question:
Is possible to make a handle when I press any of the keyboard buttons?
The SIGINT handles the Ctrl-C combination, but I want to handle if any keyboard button was pressed.
locking mutex (phtread_t type) in a signal handler function (installed by function signal()) for Linux. It seems that if the mutex has been previously locked by another thread outside the signal handler function and then the signal handler function tries to lock it, the whole process hangs.
View 5 Replies View RelatedI'm new to Unix and every signal handler algorithm I've seen is more or less a copy of what I'm trying to do.[URL] designing a signal handler with sigwait in UNIX?
View 1 Replies View RelatedI have a problem with the last point of some homework I have for an OS class. I need the program to print the pid upon execution, then for 10 seconds react to SIGUSR1, SIGUSR2 and SIGTERM. If either USR1 or USR2 is received, the 10 seconds are reset. Some of the functions I'm told to use are alarm(), pause() and signal(). The nicest way I found was to handle SIGUSR1, SIGUSR2 and SIGALRM in the parent process, with SIGALRM killing the child (with a SIGTERM). In the child a pause() (or for(; pause() would be enough for it to be alive until killed from the SIGALRM handler in the parent.
What I found is that I can't just do a wait() in the parent process, waiting for the child to be killed, since whenever the parent receives a SIGUSR1 or SIGUSR2, the right handler is called but the child exits nicely. I tried blocking/ignoring those signals in the child, since the default behaviour for SIGUSR1 and SIGUSR2 is to terminate the process, but the result is the same. The only way I could do it is using a waitpid() within a do { } while(!WIFSIGNALED(status)) since when the child gets killed with the parent's kill(), it's WIFSIGNALED, whereas when it exits after the parent handles a SIGUSR1/2, it's WIFEXITED.
P.S. What I'm doing to achieve the expected 10s window is calling alarm(10) in the parent process and again within the SIGUSR1/2 handlers. In the SIGALRM handler I kill the child and within the child I simply do a for(; pause()
I'm using a logitech quickcam pro 3000 on Ubuntu 10.04.
When I run a simple program with OpenCV to display the output from a camera I get the following output:
Code:
A window still opens with the output from the camera, but it seems very low quality and has far less pixels then it should. The camera built into my computer runs the same program with no problems.
My code for the program is simply:
Code:
One further note to make is that I still have the bad quality and low number of pixels with the logitech even when using webcam program. I can seem to find any drivers to update or anything though.
I am trying to determine the frequency of a signal coming into an imx27 processor running linux os 2.6.22 If i were using a micro i would set up a timer for a set period of time and then count up the rising edges coming in. However I am not sure how to do this with C code in linux.
View 14 Replies View RelatedIn a single main() function,so need signal handling. Use Posix Message Queue IPC mechanism , can ignore the priority and other linked list message,to implement the scenario:
View 1 Replies View Relatedi did compiled and installed kernel 3.0.0 on ubuntu 10.04 lucid lynx. well everything is fine except, a error message shown during the booting. Code: error: driver mdio-gpio already registered aborting how can i solve this error?
View 6 Replies View RelatedI have a doubt about signals in C programming. I have done this little program to explain it. It creates a child process with fork and, when the child ends, receives the SIGCHLD signal and wait for its termination.Ok, quite easy, BUT when I execute this code the SIGCHLD signal is received twice, first as an error (returns -1) and the second one to finish the child process.I don't understand the meaning of the first received signal. Why is it generated? Is the code wrong? (if you add the SIGINT and press Ctrl+C during the execution it also receives two signals instead of one)
Code: #include <stdio.h>
#include <unistd.h>
#include <string.h>
[code]....
I tried googling but didn't get any answer for this.I have a process called "abc" and it is running with PID "123".I have a putty session opened with PID "999".I am giving kill -TERM 123 from putty session.My process "abc" before dying it should catch the PID of the terminal which provided TERM signal to it.Is there any way to find this out
View 2 Replies View RelatedI have the following requirement in my module. The driver gets some data from the external device. After getting 1MB of data it has to send it to the user space application. What is the best thing to implement for this in driver.? Is it ok to implement like, after getting data, the driver will send a signal to the user space application. Then the user space application sends an ioctl to read the data. Is there any alternate, that the driver directly sends the data without the user space application asks for it.?
View 4 Replies View Related