1. If the operating system says the device exists, eg
Code:
ls >/dev/ttyS0
if that does not return an error, the serial port is configured for the OS.
2. The next part is RS232 debugging, here always start with a known working terminal and go through the different combinations with a null-modem and even a break-out-box.
We're running SCO Unix Openserver 5.05 and I'm having trouble with serial communication between the com2 serial port and a handheld device. Downloading data from Unix to the handheld works perfectly, but the other way around creates a major problem. I don't know whether it's a buffer overflow or... (1 Reply)
Hi All,
I am a begineer in Linux, I have 4 ports and 3 are operational port 1,port 2 and port 4 (when I plug in serial device I can see it working) but port 3 seems it is not working.
I am sure the hardware is fine.
when I give command
dmesg | grep tty
I get,
serial 8250:ttyS0 at... (0 Replies)
I am developing an application in c with Linux OS, where a radio modem working at baud rate 9600 will be attached to PC on serial port. More than four such units will be communicating at one time, so there may be jamming or data corruption. Each module will be transmitting Data packets less than... (2 Replies)
Hi,
I am working with solaris 9,SUN-Blade-100 and I want to communicate with the Serial port.To check whether the port is working or not.I write code and when I execute the file,then I got the output--
According to this,serial port is not found.can anyone please tell me how to configure the... (1 Reply)
Hello!
Can someone advice me which method I will use if I want to communicate with device via RS232 serial port with this requirements:
1. Serial port is opened in non-canonical mode.
2. All the time I need to check is there something to read.
3. If I have to write something I need to write it... (6 Replies)
A neighbour's Ubuntu 10.04 machine has five serial ports, one on the motherboard and four on a PCI card. However, only four cards are showing:
# dmesg | grep tty
console enabled
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:08: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
... (2 Replies)
Hi,
I have a external board connected to my serial port. I need to execute "shutdown -r now" command when system boot up. When system boots up it requires a username ans password. Then I need to run my command. I can use rc script but that is rebooting system before it asks for username and... (0 Replies)
Hi Everyone,
In my environment, I have few T5220. On the iLOM Management Card, I have both Network and Serial port are cabled, I don't have any issues while I try to connect using Network Management port, but when I try to connect the serial port for the same server which is actually connected... (3 Replies)
I am trying to write to a serial port and capture the reponse in a file -
adduser ethan dialout
The user `ethan' is already a member of `dialout'
root@meow:/home/ethan# ls -l /dev/ttyS0
crw-rw-r-- 1 ethan dialout 4, 64 Oct 7 20:55 /dev/ttyS0
$fh1 = fopen("/dev/ttyS0", "w+");... (74 Replies)
Hello,
I have an unloaded T5140 machine and want to access the ILOM for the first time and subsequently the network port after that., and then load Solaris 10 the final January 2011 build.
The first part is what confuses me -the cabling.
I am coming from a Windows machine (w/appropriate... (5 Replies)
Discussion started by: joboy
5 Replies
LEARN ABOUT SUSE
powerd
POWERD(8) System Manager's Manual POWERD(8)NAME
powerd - UPS monitoring daemon
SYNOPSIS
/sbin/powerd [tty]
DESCRIPTION
powerd monitors the serial port connected to an UPS device and will perform an unattended shutdown of the system if the UPS is on battery
longer than a specified number of minutes. powerd needs to watch a tty with modem control properties. Please refer to the powerd documen-
tation for further information.
powerd also has the capabilities of notifying other clients on the network that may have a UPS but not be connected to the serial line that
there is a power outage, and id configured through the powerd.conf file
CONFIGURATION FILE
Here is the configuration format:
Lines beginning with '#' are ignored.
MODE <mode>
specifies the mode the UPS should be in. Valid arguements are MONITOR and PEER MONITOR being the mode to actually watch a UPS serial
port, and PEER being to listen for a connection from a machine in MONITOR mode
MONITOR <device>
Specifies which device to monitor while in MONITOR mode. Specify an actual device file. Example: /dev/ttyS0
POWERFAIL <line> <high|low>
Specifies which lines on the serial ports indicate that the power is out. Valid arguements are DCD, CAR, CTS, and RNG. Also specify
if the line being HIGH or LOW indicates a power failure.
Since most people may not know this arguement, Please use the enclosed upsdetect program to automatically find this line.
NOTIFY <hostname[:port]> <password>
Specified in MONITOR mode to notify a client running in PEER mode. Specify the hostname of the machine, and optional port the daemon
is running on, And the password as specified by their LISTEN command. See below for more details.
LISTEN <hostname> <password>
Specified in PEER mode, specifies a hostname that is allowed to notify us of when the power is out, and the password they shall give
us to authenticate themselves. The 2 passwords should match on the MONITOR mode machines NOTIFY password, and the PEER modes LISTEN
password.
LISTENPORT <port>
Specified in PEER mode, specifies the port that powerd should listen on. If you use this arguement, powerd shall not default to
using port 532, and the machine in MONITOR mode must specify the port you use in their NOTIFY command.
DELAY <delayinseconds>
Specifies how many seconds before notifying init of a power outage. Note that this doesnt mean that the system will shut down in
that many seconds, as it depends on how init is configured. Init usually issues a 2 min shutdown.
USER <username>
Specifies which username to drop to from root. The program will reobtain root access only when it needs to, Like when notifying init
that the power is out. This is simply a security feature, and not needed for powerd to operate. Note: powerd must still be run ini-
tially as root. It will then drop to the user if, and only if, a username is specified.
ARGUMENTS
None: Please use the configuration file /etc/powerd.conf which can be generated with detectups. See detectups(8) for more information
FILES
/etc/powerd.conf powerd configuration file
/etc/powerstatus indicates line power status
/etc/inittab init is what actually issues the shutdown
SEE ALSO powerd(8), shutdown(8), wall(1), init(8), inittab(5).
AUTHOR
James Brents <James@nistix.com> (with parts of this man page borrowed from all over the Linux community)
POWERD(8)