Ethernet Polling vs Broadcasting on an Embedded device
I have asked to design a test system for an Ethernet enabled weather
station. At this point, these weather stations are nothing but 2 PCs
running Linux on it and they constantly read weather related
through some sensors. Eventually they will be replaced with a miniature
embedded Linux device (yet to be designed!).
I have worked extensively with 1/2 duplex RS485 networks where we poll
device and then send an acknowledgment to the device. I am not too sure
what is the best way to handle an Ethernet enabled devices. The
engineers have agreed to change the Firm...Ethernet Device
I'm considering what kind of project I'd like to do for my next year
in college. I have an idea for creating a network host device that will
work on an Ethernet LAN. Obviously, my device would need some sort of
Network Interface Card in it.
Thinking about it for about 10 seconds tho, I realised that it might
be a *very* complicated job to create a Network Interface Card,
considering things like having to implement Carrier Sense Multi-
Access/Collission Detection. Not that I'm one to shy away from a big job,
but I plan on having this project done within a year :-P
...Ethernet I/O device
I hadn't noticed this before.
It's a bit pricey but might come in handy for the solder-challenged.
...Ethernet echo device
I'm an administrator of rather distributed network and I would like
to have opportunity to ping last-to-client device to see if the link is
up and the fault is at client's computer or cable.
I would like to ask, if there's something like 'ethernet echo dongle'
- a small device to be plugged into Eth equipment (hub, switch,
whatever) and being able to be pinged from network.
I know I may plug for example a dummy D-link router (~100$ at my
place) but perhaps there's something smaller and cheaper.
Pawel Kraszewsk...Poll on device fd
Can we do poll on device fd returned by CreateFile function call?
If yes, which is callback method in device driver(on win 2k) for poll ?
select() in Windows is for sockets only.
Maxim Shatskih, Windows DDK MVP
"Tejas" <email@example.com> wrote in message
> Hi All,
> Can we do poll on device fd returned by CreateFile function call?
> If yes, which is callback method in device ...[poll] what kind of devices do you own?
From the «plus one typewriter and two dictaphones» department:
Title: Poll: You Mainly Use Desktops & Laptops
Author: Christine Hall
Date: Thu, 27 Mar 2014 13:44:05 -0400
[image 1]It’s hard to remember that it wasn’t that long ago that we only had
a couple of choices to meet our computing needs. As recently as 2007, the
year before Obama was elected, someone looking for a new computer basically
could choose betw...Adding ethernet device driver
I added Realteck 81x59 ethernet card to my pc. And also i added the
driver. The problem is while iam doing communication betn linux and
vxworks system using udp protocal i can,t send or receive messages. It
is giving as HOST UNREACHble. These two systems are directly
connected using ethernet cable.
How to check in the target shell whether the driver is added properly
added are or not?
Thanks in advance
Can you ping the vxworks system? Does any communication between the systems
work, or is just UDP behaving badly?
What type of cable is connected between the two systems? ...Ethernet device in char mode?
I am looking for a way to put an ethernet device in a sort of
"character device" mode where I can simply read and write to it
without going through the TCP/IP stack. I am trying to test some
network hardware and right now I only care that what comes out of it
is identical to what went in to it. Does anyone have any ideas?
Jeff Ward wrote:
> I am looking for a way to put an ethernet device in a sort of
> "character device" mode where I can simply read and write to it
> without going through the TCP/IP stack. I am trying to test some
> network hard...finding connected ethernet device
I have a laptop with an ethernet (eth0) and a wireless interface (eth1).
I'm using KNetworkManager to connect to networks, and in
Options>Configure>Notifications, have activated the Notification
"NetworkManager is now connected" to run a script ~/bin/connected.sh.
Thus, the script gets executed whenever I'm connecting to any network,
and handles starting some programs, e.g. ntpdate, synchronization of
This happens independently of what network interface the connection is
using. Now, I'd like to distinguish between ethernet and wireless (I...How do I communicate with 3 Ethernet devices
I am new to using ethernet and I need help writting a LabVIEW vi to communicate with 3 Omega devices. I need to open a connection to all 3 at the same time and read data from each. I am able to communicate with them individually using the TCP/IP vis (see attached vi) but I don't know how to communicate with all 3 at the same time.
Can anyone help?
Hello BertYou can simply replicate your code (copy and paste) so as to open multiple TCP/IP sessions to all three instruments as the same tim...Talking to an RS232 device over Ethernet
I would like to get data from an RS232 device. I am using a MOXA
serial/ethernet converter (works well in another app). The converter
is set up independent of VB. How do I code ASCII commands and pass to
the device? The converter has an IP address.
thanks for any help in advance
I've never used the MOXA converters but the ones that I have used
(Comtrol DeviceMaster, and others) have Winsock servers built into
them. You put a Winsock in your program and communicate that way. As
far as the ASCII commands are concerned, I would think that you'll
have to read the manuals that came wi...How to poll multiple devices in kernel ?
I'm a beginner in driver and module programming, and I need some help:
I designed a driver that need to listen at multiple devices (network
device, serial device, USB device) for incoming data.
Once received, that data should be accessible to user space through
the "read" function.
That's why I cannot use the poll/select functions from user space.
My first idea is to make a kernel thread for EACH device that do a
blocking read. When data comes, read returns and fills a global buffer
(protected with mutexes). Do you think it is a good idea?
S...Polling HW Devices with Linux
I am part of a team project in which we are requested to design a thermal
sensing system. We are asked to use Linux as the primary OS. The Thermal
Sensing Hardware is already designed. It is a pollable device (meaning you
send a request and it will give you a reply).
I am wondering if there is a Linux Messaging or Queing method that I could
use straight of of the box, Or is there a Kernel component that could do
such a Send/Receive/Reply. I have used IBM's MQs in the past but for this
task I don't think it is a viable option. I am really looking forward to
kn...question on Ethernet Device driver
1) Iam working on Philips LPC 2292 controller board, Ethernet
controller is Rtl8019 and Iam testing Rtl8019 driver on linux 2.6
Kernel.I have few Doubts.
2) If at all if a single packet comes and sits in Rx Buffer. Whether
my ethernet controller immediately raises an Interrupt or it wait for
Few seconds or milliseconds for another packets to sit in Rx Buffer
before it raises an Interrupt.
3) If at all If ISR is Executing and if Before copying a packet from
Rx Buffer to local Buffer, if few packet comes to Eth controller,
will respective packets sits in Rx Buffer or pack...Specifying ethernet device assignments
I'm upgrading a set of servers from RedHat 7.3 to Fedora Core 2
(doing a fresh install), and have run into a complication on systems
with multiple identical ethernet devices.
I've got 3 on-the-motherboard ethernet ports on the server in question -
two Intel Gigabit ports using the e1000 driver, and a 100 MB port using the
In a default installation, the system assigns the e100 to eth0, and
the e1000s are eth1 and eth1. By editing /etc/modprobe.conf and running
mkinitrd, I can "swap" the eth0 and eth2 definitions, making eth0 one of
the e1000 ports,...Talking to an RS232 device over Ethernet
Does anyone have any experience sending ASCII commands over ethernet,
through an RS232/Ethernet converter to an RS232 device?
I am coding in VB and would like to know where to start.
...SCSI device polling problem
Adaptec 2930CU adapter (bios enabled) with Seagate 4.3, IBM 9.1, Ultraplex
CDrom, and Seagate Travan 8 NS tape drive.
Cold boot, almost every cold boot, either no device found (froze at scsi
bios routine), or the IBM 9.1 was not found and scsi bios routine stops
there. Several warm boots and perhaps a cold boot or two, would clear up
and system would boot normally. Found the IBM 9.1 drive's SCSI cable
connection not fully seated. This seems to cleared up the majority of the
Now, the problem is during windows boot. Sometimes, before the windows
desktop shows, the S...device to wirelessly simulate Ethernet?
I have a Linksys wireless router, model no. WRT54GS, v.7.
I have a desktop, a laptop, and a printer connected to the router
via cat 5 cables running10Mb Ethernet. The router, in turn, connects
to a cable modem via cat 6 cable running 10Mb Ethernet. I want
to move the router, desktop, laptop, and printer upstairs in my condo,
but the cable modem must remain downstairs where the coaxial cable
enters the condo because of difficulties in running a cable upstairs.
(Please just believe me.) The problem is how to link the cable modem
downstairs to the router upstairs by wirelessly simulati...cannot ping local ethernet device
Hi TCP-IP gurus,
I have a local ethernet device configured with the IP address 10.3.0.1
and a netmask of 255.255.0.0 . When I try to ping the device, the
ICMP echo messages get routed to the local loopback interface instead
of the ethernet device itself. Is there a way to force the local
routing table to allow the packets destined for 10.3.0.1 to actually
reach that IP address instead of the 127.0.0.1 loopback interface ???
Here is the routing table configuration.
0x4 ...00 ff f6 7a a8 30 ...... TAP-Win32 Adapter V8 - Packet
================================...Communicating with an external device with Ethernet
I am trying to write a script to run an external device using
Ethernet. Is there a way that I can do this without having the
Instrument Control Toolbox (without the tcpip function)?
Thanks in advance for any help you can give me.
"Kristal Kilts" <firstname.lastname@example.org> wrote in message
>I am trying to write a script to run an external device using
> Ethernet. Is there a way that I can do this without having the
> Instrument Control Toolbox (without the tcpip function)?
> Thanks in advance for any help you...Making an ethernet-wired device wireless
I got my hands on an Onkyo Net-Tune NC-500-- a digital audio receiver
which normally connects to a PC via ethernet. I'd like to make it
connect wirelessly, but I can't find any information on how to do so.
Plug the ethernet cable into a WAP?
<email@example.com> wrote in message
>I got my hands on an Onkyo Net-Tune NC-500-- a digital audio receiver
> which normally connects to a PC via ethernet. I'd like to make it
> connect wirelessly, but I can't find any information on...Best Way to poll a Slow Device
A probably elementary question but...
I have a real-time app that needs to poll a GPIB device at a low priority periodically for data and am trying to find out the best way to do this withought hangng up the code. I am using the NI-DDK with DJGPP in protected mode DOS so I am running single threaded.
My instrument requires a command (ibcmd and ibwrt) then I read the approx 10 byte response (ibcmd and ibrd). The device is slow and I dont want my code to hang oin the ibrd function. What is the best way to poll the interface for the com...IP addresses for embedded device with ethernet
If I build an embedded system with an ethernet port and a little
embedded web server, what is the best way of identifying its IP address?
It is easy enough to get an address on most networks with DHCP, but
how does the user know so that they can type in the address in their
browser? Any ideas would be appreciated.
"David Brown" <firstname.lastname@example.org> a �crit dans le message
de news: email@example.com...
> If I build an embedded system with an ethernet port and a little embedded
> web server, what is the best way of identifying...Use of select() to poll a file (device)
I am new to wxWidgets and have a couple of questions. I will place
them in separate mails as they are quite different.
I am using wxWidgets (wxGTK) 2.8.x (various values of x) on several
Linux hosts (Ubuntu, SuSE, RedHat). My application should also work
with wxMotif and on Solaris. Possibly Windows one day too.
First question is this: without polling, how can I know when data is
ready in a file. In the past I have used something like this:
FD_ZERO( &fdset );
FD_SET( serfn, &fdset );
rc = select( serfn+1, &fdset, NULL, NULL, NULL );
/* Char read...