Hardware, Installation and Configuration
2-19
For a statically linked RCIM driver, this tunable can be specified on the GRUB boot loader
command line (
rcim.nomsi=1
). For an RCIM in module form, this tunable can be
placed in
/etc/modprobe.conf
as “
options rcim.nomsi=1
”.
System Timekeeping Configuration for GPS Support
1
If your system contains the optional GPS module, system timekeeping daemons must be
installed and configured to use the GPS receiver to synchronize the RCIM’s POSIX clock
to GPS time. The
ntpd
, daemon by itself, and the
chronyd
daemon utilizing the
gpsd
daemon are supported.
For example, to configure
ntpd
follow these steps:
1. Verify that the latest ntpd rpm is installed on the system:
#
rpm -ql ccur-ntp
If it is not installed, refer to the
RedHawk Linux Release Notes
, publication number
0898003, for instructions to install this package from the RedHawk installation
media.
2. The file
/etc/ntp.conf
supplied with the rpm contains the following
lines that are required to use the GPS.
server 127.127.8.0 mode 138 prefer #PARSE TSIP (10)+ PPS(128)
fudge 127.127.8.0 flag3 1
#enable PPS signal
The following three lines define a pool of world-wide servers that are randomly
selected at poweron for time synchronization. This feature acts as the default NTP
configuration and serves as backup to GPS. You may wish to include your local
country code before “pool” in these entries for best results; e.g.,
0.us.pool.ntp.org
. See
for more information.
server 0.pool.ntp.org
server 1.pool.ntp.org
server 2.pool.ntp.org
A block of commented out entries beginning with “logfile” is used to configure files
used for logging statistics. Uncomment the entries if you wish to enable them.
In addition to the log files,
ntpq(1)
and
ntpdc(1)
are used for NTP monitoring.
For more information about NTP, refer to the
ntpd(1)
man page and
.
At system power-on, once all data is received from the GPS satellites, accurate
timekeeping is available.
Verifying GPS Operation
1
To determine when the GPS is producing accurate system time, use the peer listing feature
of the system timekeeping daemon you are using. For example, if using
ntpd
, run
ntpq(1)
as shown below. This example utilizes command line options, however
ntpq
can also be run interactively. Refer to the man page for complete information.
Summary of Contents for RCIM
Page 1: ...Real Time Clock and Interrupt Module RCIM User s Guide 0898007 1000 March 2021...
Page 10: ...RCIM User s Guide 1 4...
Page 32: ...RCIM User s Guide 2 22...
Page 80: ...RCIM User s Guide A 28...
Page 102: ...RCIM User s Guide C 2...
