Hello,
On Fri, 8 Mar 2002, Carlos Parada wrote:
> Hi all,
>
> I would like to use the RTLinux with a GPS antenna (Trimble) for a very
> precise synchronisation. However, I'm very confused about what can be made
> in RTLinux, what kind of protocols can be used and which pins should be used
> to transport the PPS signal.
>
You should be able to use a "Real Time ISR" or a "Real Time
Periodic Task" for this. The pin that you should use depends on the
hardware and if you are using an "RTLinux ISR" or an "RTLinux Periodic
Task".
For an RTLinux ISR you should use a pin that can trigger an
interrupt. For an RTLinux Periodic Task you should be able to use any pin
that you can read from (parallel port) and poll it's value constantly. The
only problem with polling is that your precision depends on how fast you
do the polling. You may be able to connect the 0-5 V. PPS signal to the
pin in the parallel port that triggers interrupts and use a RTLinux ISR.
The only problem here is the PC's parallel port speed.
If you have money (and that knowledge) you should be able to use a
PCI card to trigger interrupts.
> I'm studying different scenarios of configuration and I would like to know
> if they are possible or not.
> The better solution for me (less expensive) is the possibility of
> synchronises the PC through a RS323 cable, receiving a TSIP and PPS signals.
> However, I don't have reached any information about the support of the
> RTLinux of this capability, or any way to make it support.
> The solution of receiving the NTP and PPS signal via RS232, is also a
> possibility (more expensive). Anybody knows if either the RTLinux supports
> this, or need any software more.
>
There is an RTLinux driver for the serial port (RS232), or you can
write your owm support for it (configure it, and read the data with an
RTLinux ISR). In the RTLinux ISR you can read the data and when you get
the PPS information start executing your code.
I hope this help.
> I'll thank very much some information and tips.
>
> Best Regards.
>
>
> Carlos Parada
>
> **********
> Carlos Fonseca Parada
> Portugal Telecom INova��o, S.A.
> MSI - Multim�dia e Servi�os IP - Redes MultiServi�o
> * Rua Eng� Jos� Ferreira Pinto Basto - 3810 Aveiro - Portugal
> Tel +351 234 403317 Ext: 1317
> Fax +351 234 420722
>
>
> > -----Original Message-----
> > From: Matt Sherer [SMTP:[EMAIL PROTECTED]]
> > Sent: Thursday, March 07, 2002 2:10 PM
> > To: '[EMAIL PROTECTED]'
> > Subject: RE: [rtl] smp installation
> >
> >
> > Yes - the kernel reflecting that source change must be actively running to
> > make any difference.
> >
> > On Thu, 7 Mar 2002, Renfroe, Patrick B wrote:
> >
> > > Made that change and got the same error when I attempted to compile
> > RTLinux.
> > > Did I need to recompile the kernel after the change?
> > >
> > > -----Original Message-----
> > > From: Matt Sherer [mailto:[EMAIL PROTECTED]]
> > > Sent: Wednesday, March 06, 2002 8:44 AM
> > > To: '[EMAIL PROTECTED]'
> > > Subject: RE: [rtl] smp installation
> > >
> > >
> > >
> > > Can you see if you can reproduce it after raising MAX_ARG_PAGES to 64 in
> > > include/linux/binfmts.h in the kernel source?
> > >
> > > On Wed, 6 Mar 2002, Renfroe, Patrick B wrote:
> > >
> > > > GNU xargs version 4.1.6
> > > > and
> > > > GNU bash, version 2.04.21(1)-release (i386-redhat-linux-gnu)
> > > >
> > > > Thanks
> > > >
> > > > -----Original Message-----
> > > > From: Matt Sherer [mailto:[EMAIL PROTECTED]]
> > > > Sent: Tuesday, March 05, 2002 8:27 AM
> > > > To: '[EMAIL PROTECTED]'
> > > > Subject: Re: [rtl] smp installation
> > > >
> > > >
> > > >
> > > > What version of xargs are you running, and what type/version of a
> > shell?
> > > >
> > > > On Tue, 5 Mar 2002, Renfroe, Patrick B wrote:
> > > >
> > > > > I am installing the 2.4.4 kernel with rtlinux 3.1 on a dual
> > processor
> > > > > (Pentium 4) machine. I finally got the 2.4.4 kernel to boot but
> > when I
> > > > > attempt to compile RTLinux I get the following error:
> > > > >
> > > > > [/usr/src/rtlinux-3.1]# make
> > > > > gcc -Wall -02 -o scripts/mkdep scripts/mkdep.c
> > > > > Kernel version 2.4.4
> > > > > for x in `find . -name Makefile`; do \
> > > > > F=`echo $x|sed 's/Makefile$//g''; \
> > > > > (cd $F; $RTL/scripts/mkdep *.c *.h *.S > .depend
> > 2>/dev/null);
> > > \
> > > > > done
> > > > > xargs: environment is too large for exec
> > > > > make: *** [.depend] Error 1
> > > > >
> > > > >
> > > > > What am I doing wrong.
> > > > >
> > > > > Thanks for any help.
> > > > > -- [rtl] ---
> > > > > To unsubscribe:
> > > > > echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR
> > > > > echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED]
> > > > > --
> > > > > For more information on Real-Time Linux see:
> > > > > http://www.rtlinux.org/
> > > > >
> > > >
> > > >
> > >
> > >
> >
> > --
> > Matt Sherer
> > FSMLabs, Inc.
> > http://www.fsmlabs.com/
> >
> > -- [rtl] ---
> > To unsubscribe:
> > echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR
> > echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED]
> > --
> > For more information on Real-Time Linux see:
> > http://www.rtlinux.org/
> -- [rtl] ---
> To unsubscribe:
> echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR
> echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED]
> --
> For more information on Real-Time Linux see:
> http://www.rtlinux.org/
>
>
--
Jose Guilberto
Robotics Researcher
245 Workman Bldg.
Dept. of Electrical Eng.
New Mexico Tech
801 Leroy Place
Socorro, NM 87801
Phone: (505) 835-5450
Fax: (505) 835-5332
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For more information on Real-Time Linux see:
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