Re: [ntp:questions] Updating NTP on FreeBSD 8.x
In article k89uho$n7$1...@dont-email.me, David Taylor david-tay...@blueyonder.co.uk wrote: Thanks, Tom, I guess I just have to wait if I use the portmaster route. At least on Windows and Linux I now know how to compile the latest tarball archive. And on FreeBSD you'd do it the exact same way as you do on GNU/Linux, and with the same disadvantages (viz., inability to use the standard package management tools to update or remove it). -GAWollman -- Garrett A. Wollman| What intellectual phenomenon can be older, or more oft woll...@bimajority.org| repeated, than the story of a large research program Opinions not shared by| that impaled itself upon a false central assumption my employers. | accepted by all practitioners? - S.J. Gould, 1993 ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Timing issue with Linux and kernel PPS?
David Taylor wrote: Which part of the article or what keyword should I be looking for? UpFront: haven't played around with the raspberry yet. My understanding was that your /dev/pps0 entry appeared too late. ( instantiated late by udev ) is the module pps-gpio loaded during system startup ? lsmod ... other ref: https://github.com/davidk/adafruit-raspberrypi-linux-pps http://www.raspberrypi.org/phpBB3/viewtopic.php?f=9t=1970 uwe ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Enclosure for Sure Electronics GPS board
Terje Mathisen terje.mathisen at tmsw.no wrote in message news:r1ten9-2qc@ntp-sure.tmsw.no... [...] http://tmsw.no/sure_gps_in_freezer_box.jpg Perfectly workable, dirt cheap. :-) That's 'Scandinavian design, priceless.' Groetjes, Maarten Wiltink ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Timing issue with Linux and kernel PPS?
On 18/11/2012 09:28, Uwe Klein wrote: David Taylor wrote: Which part of the article or what keyword should I be looking for? UpFront: haven't played around with the raspberry yet. My understanding was that your /dev/pps0 entry appeared too late. ( instantiated late by udev ) is the module pps-gpio loaded during system startup ? lsmod ... other ref: https://github.com/davidk/adafruit-raspberrypi-linux-pps http://www.raspberrypi.org/phpBB3/viewtopic.php?f=9t=1970 uwe Thanks, uwe. I've been using the pages you list as a guide. On a working (with PPS pulses) system: cat /etc/modules contains pps-gpio lsmod shows: pps_ldisc used by: 2 pps_gpio used by: 1 pps_core used by: 4 pps_gpio,pps_ldisc On a system with nothing connected to the PPS: cat /etc/modules contains pps-gpio lsmod shows: pps_gpio used by: 0 pps_core used by: 1 pps_gpio I'm unsure how to interpret the difference, or what pps_ldisc does. -- Cheers, David Web: http://www.satsignal.eu ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Updating NTP on FreeBSD 8.x
On 18/11/2012 07:49, Garrett Wollman wrote: [] And on FreeBSD you'd do it the exact same way as you do on GNU/Linux, and with the same disadvantages (viz., inability to use the standard package management tools to update or remove it). -GAWollman Thanks, Garrett, I can give that a try. -- Cheers, David Web: http://www.satsignal.eu ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Timing issue with Linux and kernel PPS?
David Taylor wrote: I'm unsure how to interpret the difference, or what pps_ldisc does. I would assume that pps_ldisc maps PPS events onto the serial port API. (Line discipline) ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
[ntp:questions] Audible signal generator (BBC pips)?
As the Raspberry Pi I am currently using as a NTP box has an audio output available, I am wondering if this otherwise unused output (on a dedicated NTP box) could be used to generate BBC style pips or other audible time signals? http://en.wikipedia.org/wiki/Greenwich_Time_Signal As I am probably not the first one to have that idea: Is there software for Linux that does this? Playing a sound file is easy. Playing it in sync with ntpd is a lot harder. /ralph ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Audible signal generator (BBC pips)?
Here is the sourcecode:
#include stdio.h
#include stdlib.h
#include unistd.h
#include string.h
#include fcntl.h
#include tgmath.h
#include sys/soundcard.h
char*SoundDev = /dev/dsp; /* device name for soundcard */
#define FSAMP 8000/* sample rate */
#define AMPLI 3 /* output amplitude */
#define TONE1 440 /* tone 1 freq */
#define DURA1 ((int)(0.1*FSAMP)) /* duration = 100 ms */
#define TONE2 440 /* tone 2 freq */
#define DURA2 ((int)(0.1*FSAMP)) /* duration = 100 ms */
#define STAR2 ((int)(0.25*FSAMP)) /* start tone2 = 250 ms */
#define RAMP((int)(0.01*FSAMP)) /* ramp-up/down = 10 ms */
#define PAUSE ((int)(1.75*FSAMP)) /* pause = 1750 ms */
#define CYCLE (STAR2+DURA2+PAUSE) /* total cycle time */
short int sample[CYCLE];
int
main (argc,argv)
int argc;
char *argv;
{
int soundfd;
int blksize;
int n;
int ampli;
double rate;
if ((soundfd = open(SoundDev,O_WRONLY)) 0) {
perror(SoundDev);
exit(1);
}
n = APF_NETWORK;/* underruns occur */
ioctl(soundfd,SNDCTL_DSP_PROFILE,n);
if (ioctl(soundfd,SNDCTL_DSP_GETBLKSIZE,blksize) 0 ||
blksize 1 || blksize 65536) {
perror(SoundDev);
exit(1);
}
if (argc 1) {
printf(%s: blocksize %d bytes\n,SoundDev,n);
printf(sample rate: %d length: %d\n,FSAMP,sizeof(sample));
printf(tone1: %dms %dHz %dms
ramp\n,1000*DURA1/FSAMP,TONE1,1000*RAMP/FSAMP);
printf(tone2: %dms %dHz %dms
ramp\n,1000*DURA2/FSAMP,TONE2,1000*RAMP/FSAMP);
printf(pause: %dms\n,1000*PAUSE/FSAMP);
}
n = 0; /* select MONO */
if (ioctl(soundfd,SNDCTL_DSP_STEREO,n) 0) {
perror(SoundDev);
exit(1);
}
n = AFMT_S16_LE;/* Little-endian signed 16bit */
if (ioctl(soundfd,SNDCTL_DSP_SETFMT,n) 0) {
perror(SoundDev);
exit(1);
}
n = FSAMP; /* sample rate */
if (ioctl(soundfd,SNDCTL_DSP_SPEED,n) 0) {
perror(SoundDev);
exit(1);
}
/* silence in buffer */
memset(sample,0,sizeof(sample));
/* tone1 */
rate = ((double)TONE1 * 2 * M_PI) / (double)FSAMP;
for (n = 0; n DURA1; n++) {
if (n RAMP)
ampli = n * AMPLI / RAMP;
else
if (n (DURA1 - RAMP))
ampli = (DURA1 - n) * AMPLI / RAMP;
else
ampli = AMPLI;
sample[n] = ampli * sin((double)n * rate);
if (argc 2) {
printf(n=%d ampli=%d sample=%d\n,n,ampli,sample[n]);
}
}
/* tone2 */
rate = ((double)TONE2 * 2 * M_PI) / (double)FSAMP;
for (n = 0; n DURA2; n++) {
if (n RAMP)
ampli = n * AMPLI / RAMP;
else
if (n (DURA2 - RAMP))
ampli = (DURA2 - n) * AMPLI / RAMP;
else
ampli = AMPLI;
sample[STAR2+n] = ampli * sin((double)n * rate);
if (argc 2) {
printf(n=%d ampli=%d sample=%d\n,STAR2+n,ampli,sample[STAR2+n]);
}
}
/* send the prepared buffer in an endless loop */
for (;;) {
if (write(soundfd,sample,sizeof(sample)) != sizeof(sample)) {
perror(SoundDev);
exit(1);
}
}
exit(0);
}
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Re: [ntp:questions] Audible signal generator (BBC pips)?
Ralph Aichinger ra...@pangea.at wrote: As the Raspberry Pi I am currently using as a NTP box has an audio output available, I am wondering if this otherwise unused output (on a dedicated NTP box) could be used to generate BBC style pips or other audible time signals? http://en.wikipedia.org/wiki/Greenwich_Time_Signal As I am probably not the first one to have that idea: Is there software for Linux that does this? Playing a sound file is easy. Playing it in sync with ntpd is a lot harder. /ralph It would actually be quite easy to output tones through the soundcard driver. I wrote a program for Linux some time ago to output an on hold signal for a PBX that had only support for external music on hold, which is quite a hassle to use legally here. You just put a sine burst as a series of sound samples in an array and write that to /dev/dsp when you like. A couple of ioctl()s set the sample rate etc. I actually used a bit of ramp-up and ramp-down on the sine amplitude to avoid the nasty clicks that can be heard on that wikipedia page, which result from sudden switch to full amplitude. To start at the right time you can use a usleep() call to wait (after inquiring the time and calculating how long to wait). Of course first you wait a second or so too short and then get the time again and re-calculate, in case the clock has drifted a bit. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Timing issue with Linux and kernel PPS?
David Taylor wrote: On 18/11/2012 09:28, Uwe Klein wrote: David Taylor wrote: Which part of the article or what keyword should I be looking for? UpFront: haven't played around with the raspberry yet. My understanding was that your /dev/pps0 entry appeared too late. ( instantiated late by udev ) is the module pps-gpio loaded during system startup ? lsmod ... other ref: https://github.com/davidk/adafruit-raspberrypi-linux-pps http://www.raspberrypi.org/phpBB3/viewtopic.php?f=9t=1970 uwe Thanks, uwe. I've been using the pages you list as a guide. On a working (with PPS pulses) system: cat /etc/modules contains pps-gpio lsmod shows: pps_ldisc used by: 2 pps_gpio used by: 1 pps_core used by: 4 pps_gpio,pps_ldisc On a system with nothing connected to the PPS: cat /etc/modules contains pps-gpio lsmod shows: pps_gpio used by: 0 pps_core used by: 1 pps_gpio I'm unsure how to interpret the difference, or what pps_ldisc does. what happens if you insmod pps_ldisc into the not ready system? you may need a call to ldattach afterwards: http://net.its.hawaii.edu/network-performance/using-praecis/ grep your way through the udev scripts !? uwe ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Audible signal generator (BBC pips)?
On 2012-11-18, Ralph Aichinger ra...@pangea.at wrote: As the Raspberry Pi I am currently using as a NTP box has an audio output available, I am wondering if this otherwise unused output (on a dedicated NTP box) could be used to generate BBC style pips or other audible time signals? http://en.wikipedia.org/wiki/Greenwich_Time_Signal As I am probably not the first one to have that idea: Is there software for Linux that does this? Playing a sound file is easy. Playing it in sync with ntpd is a lot harder. ntpd is for syncing your computer clock to UTC. Since your computer clock is now runnning at UTC, all you need is to have a program that reads your computer time and at the seconds rollover issue a sound. /ralph ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] NTP.ORG MEINBERG KEEP TIME ACCURATE to 10MS
David Taylor david-tay...@blueyonder.co.uk.invalid wrote: http://www.satsignal.eu/ntp/Raspberry-Pi-NTP.html Stick it somewhere on your LAN where there is a view through a window! A window without too much in the way of coatings on it... But for that I'd have something running here at work. rick jones -- A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail? ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
